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ALGEBRA 1

Teacher’s Name:

Unit 5 Chapter 8

This book belongs to:

UPDATED SPRING 2017

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Algebra 1 Section 8.1 Notes: Adding and Subtracting Polynomials Warm-Up Simplify. Assume that no denominator is equal to zero.

1) 70𝑎2𝑏3𝑐

14𝑎−1𝑏2𝑐 2) (-2x4y)(-3x2)2

Simplify.

3) √2163 4) 1634

Polynomial:

Examples Non-Examples

Classifying a Polynomial by the Number of Terms Monomial: Binomial: Trinomial: Finding the Degree of a Monomial and Polynomial Monomial: Polynomial: Standard Form and Leading Coefficient Standard form of a polynomial: Leading coefficient:

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Example 1: Add the polynomials. a) (7y2 + 2y – 3) + (2 – 4y + 5y2) b) (4x2 – 2x + 7) + (3x – 7x2 – 9) Example 2: Subtract the polynomials. a) (6y2 + 8y4 – 5y) – (9y4 – 7y + 2y2) b) (6n2 + 11n3 + 2n) – (4n – 3 + 5n2) Example 3: The profit a business makes is found by subtracting the cost to produce an item C from the amount earned in sales S. The cost to produce and the sales amount could be modeled by the following equations, where x is the number of items produced. C = 100x2 + 500x – 300 S = 150x2 + 450x + 200 a) Find an equation that models the profit. b) Use the above equation to predict the profit if 30 items are produced and sold.

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Algebra 1 Section 8.1 Worksheet Find each sum or difference.

1. (4y + 5) + (–7y – 1) 2. (–𝑥2 + 3x) – (5x + 2𝑥2) 3. (4𝑘2 + 8k + 2) – (2k + 3) 4. (2𝑚2 + 6m) + (𝑚2 – 5m + 7) 5. (5𝑎2 + 6a + 2) – (7𝑎2 – 7a + 5) 6. (–4𝑝2 – p + 9) + (𝑝2 + 3p – 1) 7. (𝑥3 – 3x + 1) – (𝑥3 + 7 – 12x) 8. (6𝑥2 – x + 1) – (–4 + 2𝑥2+ 8x) 9. (4𝑦2 + 2y – 8) – (7𝑦2 + 4 – y) 10. (𝑤2 – 4w – 1) + (–5 + 5𝑤2 – 3w) Determine whether each expression is a polynomial. If it is a polynomial, find the degree and determine whether it is a monomial, binomial, or trinomial.

11. 7𝑎2b + 3𝑏2 – 𝑎2b 12. 15𝑦3 + 𝑦2– 9

13. 6𝑔2ℎ3k 14. 𝑥 + 3𝑥4 − 21𝑥2

𝑥3

Write each polynomial in standard form. Identify the leading coefficient.

15. 8𝑥2 – 15 + 5𝑥5 16. 10x – 7 + 𝑥4 + 4𝑥3 17. 13𝑥2 – 5 + 6𝑥3– x 18. 4x + 2𝑥5 – 6𝑥3+ 2 19. BUSINESS The polynomial 𝑠3 – 70𝑠2 + 1500s – 10,800 models the profit a company makes on selling an item at a price s. A

second item sold at the same price brings in a profit of 𝑠3– 30𝑠2 + 450s – 5000. Write a polynomial that expresses the total profit from the sale of both items.

20. GEOMETRY The measures of two sides of a triangle are given. If P is

the perimeter, and P = 10x + 5y, find the measure of the third side.

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Algebra 1 Section 8.2 Notes: Multiplying a Polynomial by a Monomial Warm-Up Your fabulous math teacher had a really rough day and made a few errors. Please find them, correct the problems, and write out the error(s) in a complete sentence. 1) Simplify. 2) Simplify. ( ) ( )2 219 5 2 2 7 4x x x x+ + + + − ( ) ( )2 213 8 9 4 3 1x x x x− − − − +

= 26x4 + 7x2 – 2 = 9x2 – 11x - 8 Example 1: Find each product. a) 6y(4y2 – 9y – 7) b) 3x(2x2 + 3x + 5) Example 2: Simplify each expression. a) 3(2t2 – 4t – 15) + 6t(5t + 2) b) 5(4y2 + 5y – 2) + 2y(4y + 3) Example 3: Admission to the Super Fun Amusement Park is $10. Once in the park, super rides are an additional $3 each and regular rides are an additional $2. Kimbo goes to the park and rides 15 rides, of which s of those 15 are super rides.

a) Write an equation to represent the total cost Kimbo spent at the amusement park.

b) Find the cost if Kimbo rode 9 super rides.

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Example 4: Solve each equation. a) b(12 + b) – 7 = 2b + b(–4 + b) b) d(d + 3) – d(d – 4) = 9d – 16

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Algebra 1 Section 8.2 Worksheet Find each product.

1. 2h(–7ℎ2 – 4h) 2. 6pq(3𝑝2 + 4q) 3. 5jk(3jk + 2k) 4. –3rt(–2𝑡2 + 3r) 5. – 1

4m(8𝑚2 + m – 7) 6. – 2

3𝑛2(–9𝑛2 + 3n + 6)

Simplify each expression.

7. –2ℓ(3ℓ – 4) + 7ℓ 8. 5w(–7w + 3) + 2w(–2𝑤2 + 19w + 2) 9. 6t(2t – 3) – 5(2𝑡2 + 9t – 3) 10. –2(3𝑚3 + 5m + 6) + 3m(2𝑚2 + 3m + 1) 11. –3g(7g – 2) + 3(𝑔3 + 2g + 1) – 3g(–5g + 3) Solve each equation.

12. 5(2t – 1) + 3 = 3(3t + 2) 13. 3(3u + 2) + 5 = 2(2u – 2) 14. 4(8n + 3) – 5 = 2(6n + 8) + 1 15. 8(3b + 1) = 4(b + 3) – 9 16. t(t + 4) – 1 = t(t + 2) + 2 17. u(u – 5) + 8u = u(u + 2) – 4

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18. NUMBER THEORY Let x be an integer. What is the product of twice the integer added to three times the next consecutive integer?

19. INVESTMENTS Kent invested $5000 in a retirement plan. He allocated x dollars of the money to a bond account that earns 4%

interest per year and the rest to a traditional account that earns 5% interest per year. a. Write an expression that represents the amount of money invested in the traditional account. b. Write a polynomial model in simplest form for the total amount of money T Kent has invested after one year. (Hint: Each

account has A + IA dollars, where A is the original amount in the account and I is its interest rate.) c. If Kent put $500 in the bond account, how much money does he have in his retirement plan after one year? 20. COLLEGE Troy’s boss gave him $700 to start his college savings account. Troy’s boss also gives him $40 each month to add to

the account. Troy’s mother gives him $50 each month, but has been doing so for 4 fewer months than Troy’s boss. Write a simplified expression for the amount of money Troy has received from his boss and mother after m months.

21. MARKET Sophia went to the farmers’ market to purchase some vegetables. She bought peppers and potatoes. The peppers were

$0.39 each and the potatoes were $0.29 each. She spent $3.88 on vegetables, and bought 4 more potatoes than peppers. If x = the number of peppers, write and solve an equation to find out how many of each vegetable Sophia bought.

22. GEOMETRY Some monuments are constructed as rectangular pyramids. The volume of a pyramid can be found by multiplying

the area of its base B by one third of its height. The area of the rectangular base of a monument in a local park is given by the polynomial equation B = 𝑥2 – 4x – 12.

a. Write a polynomial equation to represent V, the volume of

a rectangular pyramid if its height is 10 centimeters.

b. Find the volume of the pyramid if x = 12.

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Algebra 1 Section 8.3 Day 1 Notes: Multiplying Polynomials Warm-Up 1) Simplify: −3𝑤(𝑤2 + 7𝑤 − 9) 2) Solve: 3(2𝑥 − 3) − 1 = −4(2𝑥 + 1) + 8 Example 1: Find each product using the Double Distribute method. a) (z – 6)(z – 12) b) (5x – 4)(2x + 8) c) (3x + 5)(2x – 6) Example 2: Find the product using the box/area method. 1) ( 2)( 4)x x− + 2) ( 3)( 3)x x− + 3) (2 1)( 5)x x+ + Example 3: A patio in the shape of the triangle shown is being built in Lavali’s backyard. The dimensions given are in feet. The area A of the triangle is one half the height h times the base b. Write an expression for the area of the patio.

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Example 4: The area of a rectangle is the measure of the base times the height. Write an expression for the area of the rectangle.

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Algebra 1 Section 8.3 Day 2 Notes: Multiplying Polynomials Warm-Up Find the product of the following binomials. 1) (2x – 4)(3x + 2) 2) (-4x – 8)(5x + 2) Example 5: Find the product of (3a + 4)(a2 – 12a + 1) using the Distributive Property and the box/area method.

Distributive Property Box/Area Method

Example 6: Find the product using your method of choice. a) (2b2 + 7b + 9)(b2 + 3b – 1) b) (3z + 2)(4z2 + 3z + 5)

a2 –12a 1

3a

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Algebra 1 Section 8.3 Worksheet Find each product.

1. (q + 6)(q + 5) 2. (x + 7)(x + 4) 3. (4b + 6)(b – 4) 4. (2x – 9)(2x + 4) 5. (6a – 3)(7a – 4) 6. (2x – 2)(5x – 4) 7. (m + 5)(𝑚2 + 4m – 8) 8. (t + 3)(𝑡2 + 4t + 7) 9. (2h + 3)(2ℎ2 + 3h + 4) 10. (3d + 3)(2𝑑2 + 5d – 2) 11. (3q + 2)(9𝑞2 – 12q + 4) 12. (3r + 2)(9𝑟2 + 6r + 4) 13. (3𝑛2 + 2n – 1)(2𝑛2 + n + 9) 14. (2𝑡2 + t + 3)(4𝑡2 + 2t – 2)

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GEOMETRY Write an expression to represent the area of each figure.

15. 16. 17. NUMBER THEORY Let x be an even integer. What is the product of the next two consecutive even integers? 18. GEOMETRY The volume of a rectangular pyramid is one third the product of the area of its base and its height. Find an

expression for the volume of a rectangular pyramid whose base has an area of 3𝑥2 + 12x + 9 square feet and whose height is x + 3 feet.

19. THEATER The Loft Theater has a center seating section with 3c + 8 rows and 4c – 1 seats in each row. Write an expression for the total number of seats in the center section. 20. ART The museum where Julia works plans to have a large wall mural replica of Vincent van Gogh’s The Starry Night painted in

its lobby. First, Julia wants to paint a large frame around where the mural will be. The mural’s length will be 5 feet longer than its width, and the frame will be 2 feet wide on all sides. Julia has only enough paint to cover 100 square feet of wall surface. How large can the mural be?

a. Write an expression for the area of the mural.

b. Write an expression for the area of the frame. c. Write and solve an equation to find how large the mural can be.

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Algebra 1 Section 8.4 Notes: Special Products Begin With Brain Work: Multiply out the following binomials. With a partner, discuss the patterns you found when multiplying special types of binomials. Then, use your patterns to write what you think the products of the following polynomials will be (without actually multiplying them). 1) (x + 7)2 = (x + 7)(x + 7) = 2) (x – 3)2 = (x – 3)(x – 3) = 3) (x + 9)(x – 9) =

The Patterns: 1) Squaring a Sum

Pattern: ( )2a b+ = ____ _________ ____

Example: ( )25x +

2) Squaring a Difference

Pattern: ( )2a b− = ____ _________ ____

Example: ( )25x −

3) Sum and Difference

Pattern: ( )( )+ − =a b a b ____ ____

Example: ( )( )5 5x x+ −

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Let’s try some harder ones… 1) (3c – 4)2 2) (7z + 2)2 3) (9d + 4)(9d – 4) 4) (2m – 3)2 5) (3y + 2)(3y – 2) 6) (3x + 2)2

Now you try without a calculator!

1) ( )2228 30 2= − 2) ( )2242 40 2= +

3) 231 = 4) 217 =

How does this apply? Remembering these patterns can help you do mental math. Q: What do you mean, awesome algebra teacher??

A: What is ?

∗ That is a more difficult multiplication if you do it the “long way”. ∗ Turn it into a squaring a difference problem.

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Algebra 1 Section 8.4 Worksheet Find each product.

1. (𝑛 + 9)2 2. (𝑞 + 8)2 3. (𝑥 − 10)2 4. (𝑟 − 11)2 5. (b + 6)(b – 6) 6. (z + 13)(z – 13) 7. (4𝑗 + 2)2 8. (5𝑤 − 4)2 9. (3g + 9h)(3g – 9h) 10. (4q + 5t)(4q – 5t) 11. (𝑎 + 6𝑢)2 12. (5𝑟 + 𝑝)2 13. (6ℎ − 𝑚)2 14. (4𝑏 − 7𝑣)2 15. (6a – 7b)(6a + 7b) 16. (8h + 3d)(8h – 3d) 17. (9𝑥 + 2𝑦2)2 18. (2𝑏2 – g)(2𝑏2 + g) 19. (3𝑝3 + 2𝑚)2 20. (5𝑏2 − 2𝑏)2 21. (4𝑚3 − 2𝑡)2

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22. GEOMETRY Janelle wants to enlarge a square graph that she has made so that a side of the new graph will be 1 inch more than twice the original side g. What trinomial represents the area of the enlarged graph? 23. GRAVITY The height of a penny t seconds after being dropped down a well is given by the product of (10 – 4t) and (10 + 4t).

Find the product and simplify. What type of special product does this represent? 24. BUSINESS The Combo Lock Company finds that its profit data from 2005 to the present can be modeled by the function y = 4𝑛2 + 44n + 121, where y is the profit n years since 2005. Which special product does this polynomial demonstrate? Explain. 25. STORAGE A cylindrical tank is placed along a wall. A cylindrical PVC pipe will be hidden in the corner behind the tank. See the

side view diagram below. The radius of the tank is r inches and the radius of the PVC pipe is s inches.

a. Use the Pythagorean Theorem to write an equation for the relationship between the two radii. Simplify your equation so that there is a zero on one side of the equals sign.

b. Write a polynomial equation you could solve to find the

radius s of the PVC pipe if the radius of the tank is 20 inches.

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Algebra 1 8.1 – 8.4 Review Write the polynomial in standard form. Then give the degree and leading coefficient. 1. 4 27 5 4x x x− + − + 2. 3 29 10 6x x x− + + Standard Form: Standard Form: Degree: Leading Coefficient: Degree: Leading Coefficient: Simplify each expression. Write your answer in standard form. 3. (𝑑2– d + 5) – (2d + 5) 4. (6𝑘2 + 2k + 9) + (4𝑘2– 5k) 5. (𝑥2– 3x) – (2𝑥2+ 5x) 6. –3𝑛2(–2𝑛2 + 3n + 4) 7. 4b(–5b – 3) – 2b2(𝑏2 – 7b – 4) 8. (3b + 3)(3b – 2) 9. (5a – 2)(2a – 3) 10. (m + 3)( 𝑚2 + 3m + 5) 11. (3t – 1)(𝑡2 + 2t + 4) 12. (3g + 2)(3g – 2) 13. (𝑛 + 3)2 14. (2𝑘 − 2)2

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15. Solve: 𝑤(4𝑤 + 6) + 2𝑤 = 2(2𝑤2 + 7𝑤 − 3) 16. Write an expression for the area of the triangle: 17. A parking garage charges $0.50 per daytime hour and $0.25 per hour during nights and weekends. Trent paid a total of $5.00 to park throughout the week. He also spent 2 more hours in the parking garage during the night than during the daytime. If h = the number of daytime hours in the parking garage, write and solve an equation to find out how many hours Trent parked during the day and during the night/weekend.

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Algebra 1 Section 8.5 Day 1 Notes: Using the Distributive Property (GCF) Warm-Up List the factors of each of the numbers. Then circle the greatest (biggest) one they have in common. 1) 15, 20, 45 2) 36, 18, 6 3) 21, 49, 14 4) 8, 24, 4

GCF Basics

To find the GCF of a number:

1. Ask yourself if the number will divide into the other numbers.

a. If it does, that’s your GCF!

b. If it doesn’t, keep looking. Think of (or list) factors of the ____ number.

Of those factors, find the number that will divide into all the numbers.

Example 1: Find the GCF of the numbers. a) 6, 18, 14 b) 24, 3, 12 c) 8, 24, 28 To find the GCF of a variable:

1. Take the number of variables possible.

2. If even one term does a variable, don’t include any variables in your GCF.

Example 2: Find the GCF of the variables. a) x6 + x2 + x7 b) 1 + x4 + x9 c) x + x4 + x3 - x2

Things to remember:

• Make sure your polynomial is in first.

• If your leading coefficient is , make your negative.

Example 1: Use the Distributive Property to factor each polynomial. a) 15x + 25x2 b) 4x2y2 + 2x3y3 + 8xy4 c) 9p3 + 6p6 - 12

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Additional Examples: Factor the greatest common factor out of the following polynomials. 1) 4p4 + 12p 2) 18d6 – 6d2 + 3d 3) –33x5 + 121x2 4) 5x3 – 25x2 – 35x 5) 4x2 + 36 6) 75x4y + 3x2

7) -3w4 + 21w3 8) 24t7 − 60t3 + 48t4 − 36t 9) 213514 4 −− tt 10) 4 4 3 3 2 38 4 12d q d q d q+ + 11) ccc 10255 23 +− 12) yyy 21615 23 −+ 13) yxxy 22 255 + 14) 4 3 23 24x z x z− 15) 24 210 yy −−

16) 23 2835 aa − 17) 24832 xx − 18) 26035 xxy −

19) 36243 2 ++ mm 20) 8044 4 −+ xx 21) ttt 1222 23 −+

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Algebra 1 Section 8.5 Day 2 Notes: Using the Distributive Property (Zero Product Property)

The _________ - _____________ Property

For all real numbers a and b, if ⋅ = 0a b , then either ____________ or ____________. Solutions to this equation are also known as ________________.

Example 2: Solve each equation using the zero product property. Check each solution. a) (x – 2)(4x – 1) = 0 b) 12y2 = 4y

c) (s – 3)(3s + 6) = 0 d) 40x2 – 5x = 0 Compare the four problems above to x2 + 3x = -5. What is the difference? Look at the two problems below. What is the difference? a) -a2 + 5a b) 4x2 = 2x

Partner Discussion Warm-up What do you know about the equations and solutions below? a) If 2x = 0, what do we know? b) If xy = 0, what do we know? c) If x + y = 0, what do we know?

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Example 3: A football is kicked into the air. The height of the football can be modeled by the equation h = –16x2 + 48x, where h is the height reached by the ball after x seconds. Find the values of x when h = 0. Example 4: Juanita is jumping on a trampoline in her back yard. Juanita’s jump can be modeled by the equation h = –14t2 + 21t, where h is the height of the jump in feet at t seconds. Find the values of t when h = 0.

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Algebra 1 Section 8.5 Worksheet Factor the GCF out of the following polynomials.

1. 64 – 40ab 2. 4𝑑2 + 16 3. 6𝑟2t – 3r𝑡2 4. 3x + 18 5. -2c + 10 6. 844 2 ++ yy 7. xxx 226 23 +− 8. 234 2ddd −+ 9. yyy 41210 23 +− Solve each equation. Check your solutions. 10. x(x – 32) = 0 11. 4b(b + 4) = 0 12. (y – 3)(y + 2) = 0 13. (a + 6)(3a – 7) = 0 14. 2𝑧2 + 20z = 0 15. 8𝑝2 – 4p = 0 16. 9𝑥2 = 27x 17. 18𝑥2 = 15x 18. 8𝑥2 = –26x 19. LANDSCAPING A landscaping company has been commissioned to design a triangular flower bed for a mall entrance. The final dimensions of the flower bed have not been determined, but the company knows that the height will be two feet less than the base. The area of the flower bed can be represented by the equation A = 1

2𝑏2 – b.

a. Write this equation in factored form.

b. Suppose the base of the flower bed is 16 feet. What will be its area?

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20. PHYSICAL SCIENCE Mr. Alim’s science class launched a toy rocket from ground level with an initial upward velocity of 60

feet per second. The height h of the rocket in feet above the ground after t seconds is modeled by the equation h = 60t – 16𝑡2. How long was the rocket in the air before it returned to the ground?

21. PHYSICS According to legend, Galileo dropped objects of different weights from the so-called “leaning tower” of Pisa while

developing his formula for free falling objects. The relationship that he discovered was that the distance d an object falls after t seconds is given by d = 16𝑡2 (ignoring air resistance). This relationship can be found in the equation h = 4t – 16𝑡2, where h is the height of an object thrown upward from ground level at a rate of 32 feet per second. Solve the equation for h = 0.

22. SWIMMING POOL The area A of a rectangular swimming pool is given by the equation A = 12w – 𝑤2, where w is the width of

one side. Write an expression for the other side of the pool. 23. CONSTRUCTION Unique Building Company is constructing a triangular roof truss for a building. The workers assemble the

truss with the dimensions shown on the diagram below. Using the Pythagorean Theorem, find the length of the sides of the truss. 24. VERTICAL JUMP Your vertical jump height is measured by subtracting your standing reach height from the height of the

highest point you can reach by jumping without taking a running start. Typically, NBA players have vertical jump heights of up to 34 inches. If an NBA player jumps this high, his height h in inches above his standing reach height after t seconds can be modeled by h = 162t – 192𝑡2. Solve the equation for h = 0 and interpret the solution. Round your answer to the nearest hundredth.

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Algebra 1 Section 8.6 Day 1 Notes: Factoring 𝒙𝟐 + 𝒃𝒙 + 𝒄 Warm-Up Multiply out the following binomials. With a partner, discuss any patterns you notice with the numbers in the initial problem and end result. How could you work backwards? 1) (x + 2)(x + 3) 2) (x – 9)(x + 7) 3) (x – 11)(x – 3) What is a Factor? Let’s start simple…how would you explain what the factors of 12 are? Factor - Example 1: Factor each polynomial. a) x2 + 7x + 12 b) x2 – 12x + 27 c) x2 + 3x – 18

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Algebra 1 Section 8.6 Day 2 Notes: Factoring 𝒙𝟐 + 𝒃𝒙 + 𝒄 Warm-Up Factor each of the following expressions. 1) x2 – 6x – 16 2) x2 + 2x – 8 Example 2: Factor each polynomial. Remember to check for the GCF first!! a) 2𝑥2 + 12𝑥 + 16 b) −6𝑥 − 45 + 3𝑥2 c) 2𝑥3 + 14𝑥2 + 24𝑥 Extra Practice: Factor each polynomial. Remember to check for the GCF first!! a) x2 – 10x + 16 b) x2 – x – 20 c) 𝑥3 + 5𝑥2 + 6𝑥 d) 𝑥2 − 7𝑥 − 18 e) 5𝑥2 + 25𝑥 + 20 f) 4𝑥2 − 4𝑥 − 8 g) 𝑥2 − 7𝑥 + 10 h) 𝑥2 + 13𝑥 + 12 i) 2𝑥2 + 2𝑥 − 4

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Algebra 1 Section 8.6 Day 3 Notes: Solving 𝒙𝟐 + 𝒃𝒙 + 𝒄 = 𝟎 Warm-Up Factor each of the following expressions. 1) 𝑥2 − 7𝑥 + 10 2) 2𝑥2 + 4𝑥 − 30 Example 3: Solve each equation. Check your solutions. a) x2 + 2x = 15 b) x2 – 20 = x c) x2 + 4x + 27 = 24 Example 4: Solve each equation. Check your solutions. a) 4𝑥2 + 4𝑥 = 24 b) 2𝑥2 − 6𝑥 = 20 c) 2𝑥2 + 60 = −22𝑥 Example 5: The Property Brothers want to build a new art studio that has three times the area of their old studio by increasing the length and width by the same amount. What should be the dimensions of the new studio?

Example 6: Hermoine has a 4 × 6 photograph. She wants to enlarge the photograph by increasing the length and width by the same amount. What dimensions of the enlarged photograph will produce an area twice the area of the original photograph?

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Algebra 1 Section 8.6 Worksheet Factor each polynomial.

1. 𝑎2 + 10a + 24 2. ℎ2 + 12h + 27 3. 3𝑥2 + 42x + 99 4. 𝑔2 – 2g – 63 5. 𝑤2 + w – 56 6. 𝑏2 + 4b – 32 7. 2𝑛2 – 6n – 56 8. 𝑡2 + 4t – 45 9. 4𝒛𝟐 – 44z + 120 10. 𝑞2 – q – 56 11. 𝑥2 – 6x – 55 12. 32 + 18r + 𝑟2

Solve each equation. Check the solutions.

13. 𝑥2 + 17x + 42 = 0 14. 𝑝2 + 5p – 84 = 0 15. 𝑘2 + 3k – 54 = 0 16. 𝑛2 + 4n = 32 17. 34r + 2𝑟2 = –104 18. 80 + 𝑎2 = 18a 19. 3𝑡2 – 78t = 168 20. 𝑧2 – 14z = 72 21. 𝑦2 – 84 = 5y

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22. CONSTRUCTION A construction company is planning to pour concrete for a driveway. The length of the driveway is 16 feet longer than its width w.

a. Write an expression for the area of the driveway.

b. Find the dimensions of the driveway if it has an area of 260 square feet.

23. WEB DESIGN Janeel has a 10-inch by 12-inch photograph. She wants to scan the photograph, then reduce the result by the same amount in each dimension to post on her Web site. Janeel wants the area of the image to be one eighth that of the original photograph.

a. Write an equation to represent the area of the reduced image.

b. Find the dimensions of the reduced image.

24. COMPACT DISCS A compact disc jewel case has a width 2 centimeters greater than its length. The area for the front cover is 168 square centimeters. The first two steps to finding the value of x are shown below. Solve the equation and find the length of the case.

Length × width = area

x(x + 2) = 168

𝑥2 + 2x – 168 = 0

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Algebra 1 Section 8.7 Day 1 Notes: Factoring 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄 Warm-Up Solve each of the following quadratic equations. 1) 𝑥2 + 8𝑥 = −12 2) 3𝑥2 + 12𝑥 + 9 = 0 3) 3𝑥2 + 5𝑥 + 2 = 0 What’s different about the third problem?

Options for Factoring when a≠ 𝟏

Logic Box Method Slide & Divide Example 1: Factor each trinomial. Remember to look for the GCF first!! a) 5x2 + 27x + 10 b) 7x2 + 29x + 4 c) 4𝑥2 + 10𝑥 + 4 d) 2x2 – x – 1

Steps for Slide and Divide 1. Slide the a over to c and _______________ them together. 2. Rewrite in the form 𝑥2 + 𝑏𝑥 + (𝑎𝑎). 3. Factor using _____________________. 4. Divide by a. 5. _________________ any fractions. 6. Slide any ____________________ back in front of the x.

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Prime Polynomial: a polynomial that cannot be written as a product of two polynomials with coefficients that are _______________. Example 2: Factor each trinomial. Determine whether the polynomial is prime. a) 3x2 + 7x – 5 b) 3x2 – 5x + 3 Extra Practice: Factor each trinomial. Remember to look for the GCF first!! a) 2𝑥2 + 5𝑥 + 3 b) 4x2 + 24x + 32 c) 2x2 + 14x + 20 d) 4𝑥2 + 3𝑥 − 1 e) 5𝑥2 + 19𝑥 + 1 f) 4𝑥2 + 15𝑥 + 9

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Algebra 1 Section 8.7 Day 2 Notes: Solving 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄 = 𝟎 Warm-Up Factor each of the following expressions. 1) 3𝑥2 + 5𝑥 + 2 2) 6𝑥2 − 4𝑥 − 16 Example 3: Solve each equation. Check your solutions. a) 3𝑥2 − 4𝑥 = 15 b) 3𝑥2 + 30 = −21𝑥 c) 3𝑥2 + 13𝑥 + 9 = −1 d) 8𝑥2 + 10𝑥 − 11 = 3𝑥 − 10

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Rally Coach ____________________ ___________________

1) Factor 2x2 + 7x + 6 2) Solve 3x2 + 5x + 2 = 0

3) Factor 2x2 – 5x – 3

4) Solve 3x2 + 10x = 8

5) Factor 3x2 + 10x + 3 6) Solve 2x2 + 3x – 5 = 0

7) Factor 3x2 + 9x – 12 8) Solve 2x2 - 2x = 4

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Algebra 1 Section 8.7 Day 3 Notes: Solving 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄 = 𝟎 (Vertical Motion) Warm-Up 1) Solve 10𝑥2 − 13𝑥 + 3 = 0 2) Solve 10𝑥2 + 12 = 26𝑥 Example 4: When Mario jumps over a hurdle, his feet leave the ground traveling at an initial upward velocity of 12 feet per second. Find the time t in seconds it takes for Mario’s feet to reach the ground again. Use the equation h = –16t2 + vt + h0, where h is height in feet, t is time in seconds, v is the initial upward velocity in feet per second, and ho is the initial height in feet. Example 5: Mr. Nguyen’s science class built a model rocket for a competition. When they launched their rocket outside the classroom, the rocket cleared the top of a 60-foot high pole and then landed in a nearby tree. If the launch pad was 2 feet above the ground, the initial velocity of the rocket was 64 feet per second, and the rocket landed 30 feet above the ground, how long was the rocket in flight? Use the equation h = –16t2 + vt + h0,

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Vertical Motion Extra Problems

ℎ = −16𝑡2 + 𝑣𝑡 + ℎ𝑜

1. A startled armadillo jumps straight into the air with an initial vertical velocity of 14 feet per second. After how many seconds does it land on the ground? 2. A cat leaps from the ground into the air with an initial vertical velocity of 11 feet per second. After how many seconds does the cat land on the ground?

3. An athlete throws a discus from an initial height of 6 feet and with an initial vertical velocity of 46 feet per second. After how many seconds does the discus hit the ground?

4. You throw a ball into the air with an initial vertical velocity of 31 feet per second. The ball leaves your hand when it is 6 feet above the ground. You catch the ball when it reaches a height of 4 feet. After how many seconds do you catch the ball?

5. You hit a baseball straight up into the air. The baseball is hit with an initial vertical velocity of 80 feet per second when it is 3 feet off the ground. After how many seconds does the ball reach a height of 99 feet?

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Algebra 1 Section 8.7 Worksheet Factor each polynomial, if possible. If the polynomial cannot be factored using integers, write prime. 1. 2𝑏2 + 10b + 12 2. 3𝑔2 + 8g + 4 3. 4𝑥2 + 4x – 3

4. 8𝑏2 – 5b – 10 5. 6𝑚2 + 7m – 3 6. 10𝑑2 + 17d – 20

7. 12𝑦2 – 4y – 5 8. 14𝑘2 – 9k – 18 9. 8𝑧2 + 20z – 48

10. 12𝑞2 + 34q – 28 11. 18ℎ2 + 15h – 18 12. 12𝑝2 – 22p – 20

Solve each equation. Check the solutions.

13. 3ℎ2 + 2h – 16 = 0 14. 15𝑛2 – n = 2 15. 8𝑞2 – 10q + 3 = 0

16. 6𝑏2 – 5b = 4 17. 10𝑟2 – 21r = –4r + 6 18. 10𝑔2 + 10 = 29g

19. 12𝑥2 – 1 = –x 20. 8𝑎2 – 16a = 6a – 12 21. 18𝑎2 + 10a = –11a + 4

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22. DIVING Lauren dove into a swimming pool from a 15-foot-high diving board with an initial upward velocity of 8 feet per second. Find the time t in seconds it took Lauren to enter the water. Use the model for vertical motion given by the equation h = –16𝑡2 + vt + ho, where h is height in feet, t is time in seconds, v is the initial upward velocity in feet per second, and ho is the initial height in feet. (Hint: Let h = 0 represent the surface of the pool.) 23. BASEBALL Brad tossed a baseball in the air from a height of 6 feet with an initial upward velocity of 14 feet per second. Enrique

caught the ball on its way down at a point 4 feet above the ground. How long was the ball in the air before Enrique caught it? Use the model of vertical motion from Exercise 22.

24. BREAK EVEN Breaking even occurs when the revenues for a business equal the cost. A local children’s museum studied their

costs and revenues from paid admission. They found that their break-even time is given by the equation 2ℎ2 – 2h – 24 = 0, where h is the number of hours the museum is open per day. How many hours must the museum be open per day to reach the break even point?

25. FURNITURE The student council wants to purchase a table for the school lobby. The table comes in a variety of dimensions, but

for every table, the length is 1 meter greater than twice the width. The student council has budgeted for a table top with an area of exactly 3 square meters.

Find the width and length of the table they can purchase.

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Algebra 1 Factoring/Solving All Types Homework (8.5 – 8.7) Factor the expression or solve the equation. Show all work. 1.) x2 – 5x – 14 2.) 4x3 – 12x2 3.) 2x2 + 3x – 9 4.) x2 + 5x – 24 = 0 5.) 3x2 – 8x + 4 = 0 6.) 4x2 + 10x + 6 = 0 7.) 6x3 + 14x2 + 4x 8.) 2x3 + 2x2 – 12x

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Algebra 1 8.5 – 8.7 Review Determine the GCF for each of the following polynomials. Then, factor out the GCF. 1. 6𝑥2 + 3𝑥 2. −8𝑥2 + 6 Factor the polynomial completely. If the polynomial cannot be factored using integers, write prime. 3. 6𝑥2 + 5𝑥 − 6 4. 𝑥2 + 2𝑥 − 24 5. 𝑥2 − 4𝑥 + 24 6. 15𝑥2 − 27𝑥 − 6 7. 2𝑥3 + 12𝑥2 + 16𝑥 8. 2𝑥2 + 11𝑥 + 5 Solve the equation. 9. 𝑥(𝑥 − 3) = 0 10. 𝑥2 + 𝑥 = 2

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11. 3𝑥2 − 8𝑥 − 16 = 0 12. 3𝑥2 + 18 = −15𝑥 13. −3𝑥2 = −9𝑥 14. The length of a rectangle is 3 centimeters more than the width. The area of the rectangle is 40 square

centimeters. What is the length? 15. A pumpkin is launched into the air from ground level with an initial vertical velocity of 80 feet per second. How long does it take to hit the ground again? Use the equation ℎ = −16𝑡2 + 𝑣𝑡 + ℎ0

x + 3

x

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Algebra 1 Section 8.8 Notes: Differences of Two Squares Difference of Two Squares Pattern: a2 – b2 = Example: x2 – 9 = Example 1: Factor each polynomial. a) m2 – 64 b) 18y2 – 8z2 c) 25a2 – 36b2 Example 2: Factor each polynomial. a) 3b3 – 27b b) 5x3 – 20x Example 3: Factor each polynomial. a) y4 – 625 b) y4 – 16

Warm Up: Take a look at these 3 examples. They have been multiplied out using the double-distribute method. a) (x + 9)(x – 8) = x2 – 8x + 9x – 72 b) (x – 9)(x – 9) = x2 – 9x – 9x + 81 c) (x + 9)(x – 9) = x2 – 9x + 9x – 81

= x2 + x – 72 = x2 – 18x + 81 = x2 – 81 Discussion Questions:

1) How is the final answer in (c) different from (a) and (b)?

2) What do you think contributes to this difference in each of the original problems? Pay attention to differences and similarities between signs and numbers.

3) Let’s look closer at (c). How could we work backwards and start with x2 – 81 and end up with (x + 9)(x – 9) while “skipping” the middle step?

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Example 4: Solve the equation. a) 𝑥2 − 81 = 0 b) 𝑥2 − 64 = 0 c) 9𝑥2 − 25 = 0

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Algebra 1 Section 8.8 Worksheet Factor each polynomial, if possible. If the polynomial cannot be factored, write prime.

1. 𝑘2 – 100 2. 81 – 𝑟2 3. 16𝑝2 – 36 4. 4𝑥2 + 25 5. 144 – 9𝑓2 6. 36𝑔2 – 49ℎ2 7. 121𝑚2 – 144𝑝2 8. 32 – 8𝑦2 9. 24𝑎2 – 54𝑏2 10. 32𝑡2 – 18𝑢2 11. 9𝑑2 – 32 12. 36𝑧3 – 9z 13. 45𝑞3 – 20q 14. 100𝑏3 – 36b 15. 3𝑡4 – 48𝑡2 Solve each equation by factoring. Check your solutions.

16. 4𝑦2 – 81 = 0 17. 64𝑝2 – 9 = 0 18. 98𝑏2 – 50 = 0 19. LOTTERY A state lottery commission analyzes the ticket purchasing patterns of its citizens. The following expression is

developed to help officials calculate the likely number of people who will buy tickets for a certain size jackpot.

81𝑎2– 36𝑏2

Factor the expression completely. 20. OPTICS A reflector on the inside of a certain flashlight is a parabola given by the equation y = 𝑥2– 25. Find the points where the

reflector meets the lens by finding the values of x when y = 0.

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21. BALLOONING The function f (t) = –16𝑡2+ 576 represents the height of a freely falling ballast bag that starts from rest on a

balloon 576 feet above the ground. After how many seconds t does the ballast bag hit the ground? 22. DECORATING Marvin wants to purchase a rectangular rug. It has an area of 80 square feet. He cannot remember the length and

width, but he remembers that the length was 8 more than some number and the width was 8 less than that same number. a. Write a quadratic equation using the information given. b. What are the length and width of the rug?

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Algebra 1 Section 8.9 Day 1 Notes: Perfect Squares Warm-Up Factor or solve the following: 1) x2 – 169 2) 25y2 + 49 3) 81x2 – 9 = 0 Perfect Square Trinomial: a trinomial that is the square of a binomial. Pattern I Pattern 2 Pattern: a2 + 2ab + b2 = Pattern: a2 – 2ab + b2 = Example: 4x2 + 12x + 9 = Example: 4x2 – 12x + 9 = Example 1: Determine whether each trinomial is a perfect square trinomial. Write yes or no. If so, factor it. a) 25x2 – 30x + 9 b) 49y2 + 42y + 36 c) 9x2 – 12x + 16 d) 49x2 + 28x + 4 Example 2: Solve each equation. Check your solution. a) 4x2 + 36x = –81 b) 9x2 – 30x + 25 = 0

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Example 3: After factoring out the GCF, circle the problems that are “perfect square trinomials” or “difference of two squares”. Factor using the patterns we learned about, if possible. Otherwise, factor using a different method. a) 6x2 – 96 b) 4x2 + 10x + 6 c) –3x2 + 12x – 12 d) 14x + 12 + 2x2 e) –x2 – 12x – 36 f) –27 + 12y2

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Algebra 1 Section 8.9 Day 2 Notes: Perfect Squares Warm-Up Factor each of the following: 1) 𝑥2 − 8𝑥 − 9 2) 25𝑥2 − 9 3) 16𝑥2 − 40𝑥 + 25 Solve for x. 1. 𝑥2 = 100 2. 2𝑥2 = 32 3. 2𝑥2 + 5 = 77 4. 10 + 2𝑥2 = 28 Square Root Property: When do I use this? a) 4𝑥2 − 81 = 0 b) 𝑥2 − 6𝑥 − 16 = 0 Example 4: You tripped over your feet while walking to Miss Day’s class and dropped all of your books. How long does it take for embarrassment to set in (aka until the books hit the ground)? You were holding the books __________ feet above the ground when you dropped them. A model for the height h in feet of an object dropped from an initial height of h0 feet is h = –16t2 + h0 , where t is the time in seconds after the object is dropped. Use this model to determine approximately how long it took for the book to reach the ground.

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Algebra 1 Section 8.9 Worksheet Determine whether each trinomial is a perfect square trinomial. Write yes or no. If so, factor it.

1. 𝑚2 + 16m + 64 2. 9𝑟2 – 6r + 1 3. 4𝑦2 – 20y + 25 4. 16𝑝2 + 24p + 9 5. 25𝑏2 – 4b + 16 6. 49𝑘2 – 56k + 16 Factor each polynomial, if possible. If the polynomial cannot be factored, write prime.

7. 3𝑝2 – 147 8. 6𝑥2 + 11x – 35 9. 50𝑞2 – 60q + 18 10. 6𝑡3 – 14𝑡2 – 12t 11. 6𝑑2 – 18 12. 30𝑘2 + 38k + 12 13. 15𝑏2 – 24bf 14. 12ℎ2 – 60h + 75 15. 9𝑛2 – 30n – 25 16. 7𝑢2 – 28𝑚2 17. 𝑤4 – 8𝑤2 – 9 18. 16𝑎2 + 72ad + 81𝑑2 Solve each equation. Check the solutions.

19. 4𝑘2 – 28k = –49 20. 50𝑏2 + 20b + 2 = 0 21. 𝑥2 + 12x + 36 = 25 22. 𝑦2 – 8y + 16 = 64 23. (ℎ + 9)2 = 3 24. 𝑤2 – 6w + 9 = 13

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25. PICTURE FRAMING Mikaela placed a frame around a print that measures 10 inches by 10 inches. The area of just the frame itself is 69 square inches. What is the width of the frame?

26. CONSTRUCTION The area of Liberty Township’s square playground is represented by the trinomial 𝑥2 – 10x + 25. Write an expression using the variable x that represents the perimeter.

27. AMUSEMENT PARKS Funtown Downtown wants to build a vertical motion ride where the passengers are launched straight

upward from ground level with an initial velocity of 96 feet per second. The ride car’s height h in feet after t seconds is h = 96t – 16𝑡2. How many seconds after launch would the car reach 144 feet?

28. BUSINESS Saini Sprinkler Company installs irrigation systems. To track monthly costs C and revenues R, they use the following

functions, where x is the number of systems they install. R(x) = 8𝑥2+ 12x + 4 C(x) = 7𝑥2+ 20x – 12

The monthly profit can be found by subtracting cost from revenue. P(x) = R(x) – C(x)

Find a function to project monthly profit and use it to find the break-even point where the profit is zero. 29. GEOMETRY Holly can make an open-topped box out of a square piece of cardboard by cutting 3-inch squares from the corners

and folding up the sides to meet. The volume of the resulting box is V = 3𝑥2– 36x + 108, where x is the original length and width of the cardboard.

a. Factor the polynomial expression from the volume equation.

b. What is the volume of the box if the original length of each

side of the cardboard was 14 inches? c. What is the original side length of the cardboard when the

volume of the box is 27 in3?

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Algebra 1 Extra Factoring Practice Factor each expression completely. 1. 2. 212 32 5x x+ + 3. 4. 5. 2 4 3x x− + 6. 7. 24 3 7x x− − 8. 9. 10. 11. 12.