Algebra 1 Review
Casey Andreski
Bryce Lein
In the next slides you will review:
Solving 1st power equations in one variable
A. Don't forget special cases where variables cancel to get {all reals} or
B. Equations containing fractional coefficients
C. Equations with variables in the denominator – remember to throw out answers that cause division by zero
Special cases
Cancel variables
3x+2=3(x-1) distribute
3x+2=3x-3 subtract 3x
2=-3 finished
Fractional Coefficient
• 1/2x - 3 + 1/3x = 2 multiply by a common denominator
• 3x - 18 + 2x = 12 add like terms
• 5x = 40 divide by 5
• X = 8 finished
Variables in the denominator
• 5/x + 3/4 = 1/2 Multiply by a common denominator
• 5 + 3/4x = 1/2x group like terms
• 5 = -3/4x + 2/4x add like terms
• 5 = -1/4x multiply by common denominator
• -20 = x
Properties
Addition Property (of Equality)
Multiplication Property (of Equality)
Example: a + c = b + c
Example:
If a = b then a x c = b x c.
Reflexive Property (of Equality)
Symmetric Property (of Equality)
Transitive Property (of Equality)
Example:
a = a
Example:
a = b then b = a
Example:
If a = b and b = c, then a = c
Associative Property of Addition
Associative Property of Multiplication
Example:
a + (b + c) = (a + b) + c
Example:
a x (b x c) = (a x b) x c
Commutative Property of Addition
Commutative Property of Multiplication
Example:
a + b = b + a
Example:
a x b = b x a
Distributive Property (of Multiplication over Addition
Example:
a x (b + c) = a x b + a x c
Prop of Opposites or Inverse Property of Addition
Prop of Reciprocals or Inverse Prop. of Multiplication
Example:
a + (-a) = 0
Example:
(b)1/b=1
Identity Property of Addition
Identity Property of Multiplication
Example:
y + 0 = y
Example: b x 1= b
Multiplicative Property of Zero
Closure Property of Addition
Closure Property of Multiplication
Example: a x 0 = 0
Example: 2 + 5 = 7
Example: 4 x 5 = 20
Product of Powers Property
Power of a Product Property
Example: 42 x 44 = 46
Example: (2b)3 = 23 x b3 = 8b3
Quotient of Powers Property
Power of a Quotient Property
Example: 54/53 = 625/125 or 54-3 = 51 = 5
Example: (4/2)2 = 42/22 = 4
Zero Power Property
Negative Power Property
Example: a0 = 1
Example: a-6 = 1/a6
Zero Product Property
Example: If ab = 0 , then either a = 0 or b = 0.
Product of Roots Property
Quotient of Roots Property
a b a b
a a
bb
Root of a Power Property
Power of a Root Property
Example:
Example:
2x x
2x
Now you will take a quiz!Look at the sample problem and give the name of the property illustrated.
1. 14 + 3 = 3 + 14
Click when you’re ready to see the answer.
Answer: Commutative Property (of Addition)
17 = 17
In the next slides you will review:
Solving 1st power inequalities in one variable. (Don't forget the special cases of {all reals} and )A. With only one inequality signB. ConjunctionC. Disjunction
With only one inequality sign
3 + x < 3 + 2
Click when ready to see the answerer
2
X < 2
Conjunction
3+5<1+x>-2-1Click when you’re ready to see the answer.
8<1+x>-2-1
7<x>-4
7-4
Disjunction 3x>(14+4) or x<3-4 Click to see the answer
3x>18 or x<-1
X>6
-1 6
In the next slides you will review:
Linear equations in two variablesLots to cover here: slopes of all
types of lines; equations of all types of lines, standard/general form, point-slope form, how to graph, how to find intercepts, how and when to use the point-slope formula, etc. Remember you can make lovely graphs in Geometer's Sketchpad and copy and paste them into PPT.
Slope
Finding the slope with 2 given points
m = Slope
Example:
(9,-3) (6,2)
2-9 -7
6+3 9
Click for an
example
Equations of Lines
Slope intercept form- Y = Mx + B
Standard form – Ax + By = C
Point slope form- Y – Y1 = M (X – X1)
Graphing Lines Point Slope- use this when you only have 2
points.
First : find the slope
Next put the equation into point slope form:
y-y1=m(x-x1)
Example: (3,5) (2,1)
Slope: = 4
Y-5=4(x-3) = y-5=4x-12 = y=4x-7
5 1
3 2
Graphing Lines
Slope intercept - y=-3x+7
7= y intercept
-3 = slope
Graphing Lines
Standard form - 3x + 2y = 6
Set x to zero to find y
Set y to zero to find x
Points : (2,0) (0,3)
In the next slides you will review:
Linear SystemsA. Substitution MethodB. Addition/Subtraction
Method (Elimination ) C. Check for understanding
of the terms dependent, inconsistent and consistent
Substitution Method 4x-5y=12
Y=2x-8
Put (2x-8) in for y for the top equation
Click for solution 4x-5(2x-8)=12 Distribute
4x-10x+40=12 add/subtract common terms
-6x=28 Divide
X= -3/14
Addition/Subtraction Method (Elimination )
3x+5y=7
2x-4y=5
Multiply both equations to get either x or y to cancel
2(3x+5y)=7 = 6x+10y=14
3(2x-4y)=5 = 6x-12y=15 Subtract
22y=-1 Divide by 22
y= -1/22
Terms
Dependent- both same line (Infinite solutions)
Inconsistent- parallel lines (No solutions)
Consistent- Intersecting lines (One solution)
In the next slides you will review:
Factoring – since we just completed the Inspiration Project on this topic, just summarize all the factoring methods quickly. Note that you will be using your factoring methods in areas 7 & 8 below so no need to include extra practice problems here.
Factoring Binomials
difference of squares 49x4-9y2
(7x2+3y) (7x2-3y) sum and diff of squares a3-27 (a-3) (a2+3a+9)
click for answers
Factoring Trinomials
GCF 2b+4b2+8b
2b(1+2b+4)
Reverse foil x2+5x+6
(x+3) (x+2)
PST 4x2-20x+25
(2x-5)2
Click for answers
4 or More Click for answers
3 by [(x1 x2+8x+16-3y2
(x+4)2-3y2
[(x+4)-3y] +4)-3y] 2 by 2 c3+bc+2c2+2b
c2(c+2)+b(c+2)
(c2+b) (c+2)
In the next slides you will review:
Rational expressions – try to use all your factoring methods somewhere in these practice problems
A. Simplify by factor and cancel
B. Addition and subtraction of rational expressions
C. Multiplication and division of rational expressions
Factor and Cancel
16
42
x
x4
1
x=
Addition and subtraction of rational expressions
416
22
x
x
x
x
16
)4(22
x
xxx16
422
2
x
xxx
16
62
2
x
xx
Click to see steps
Multiplication and division of rational expressions
6
3
6
442
2
x
x
xx
xx
6
2
6
3
)3)(2(
)2)(2(
x
x
x
x
xx
xx
Click to see answer
Division is multiplication of the reciprocal
In the next slides you will review:
FunctionsA. What does f(x) mean? Are all
relations function?B. Find the domain and range of a
function.C. Given two ordered pairs of data,
find a linear function that contains those points.
D. Quadratic functions – explain everything we know about how to graph a parabola
Functions
f(x) means that f is a function of x
All functions are relations but not all relations are functions
A function is 1 to 1 which means for each input there is exactly one output
Functions
Domain- Set of inputs
Range- Set of outputs
f(x)=2x-1
Domain – all real numbers
Range – all real numbers
Functions
(1,1) and (0,-1)
Are two ordered pairs of the
linear function f(x)=2x-1
Quadratic functions
f(x)=ax2+bx+c
Vertex x= , then solve for f(x)
X-intercepts set f(x) equal to zero factor and solve for x
y-intercepts Set x to zero and solve for f(x)
line of symmetry the line of
a
b
2
a
b
2
a
b
2
In the next slides you will review:
Simplifying expressions with exponents – try to use all the power properties and don't forget zero and negative powers.
Exponents
www.basic-mathematics.com
In the next slides you will review:
Simplifying expressions with radicals – try to use all the root powers and don't forget rationalizing denominators
Expressions with Radicals
2
2
22
21
2
1
2322282
2
1
4
1
8
2
41682
In the next slides you will review:
Minimum of four word problems of various types. You can mix these in among the topics above or put them all together in one section. (Think what types you expect to see on your final exam.)
Word Problem
You drove 180 miles at a constant rate and it took you t hours. If you would have driven 15 mph faster you would have saved an hour. What was your rate?
180 = rt → t = 180/r
180 = (r +15)(t –1)→180= (r+15)(180/r – 1)
180r = (r+15)(180 – r)→180r=180r-r2+2700-15r
r2+15r-2700=0→(r-45)(r+60)=0
r=45 your rate was 45 mph
Word Problem
If Joe can shovel his driveway in 2 hours and Bill can do it in 3 hours, how long will it take for both of them to shovel the driveway.
5
11
65
623
132
x
x
xx
xx
Word Problem
If 2 t-shirts and 3 pairs of shorts cost $69, and 2 pair of shorts are $30. How Much is a t-shirt?
2t+3s=69
2s=30
s=15
2t+3(15)=69
2t+45=69
2t=24
t=12
Word ProblemAfter bill lost his cell phone he had to pay his
parents 28% of the cost to buy a new phone. Bill had to pay $21.28. What was the price of the phone
76$
7628.
28.21
28.2128.
p
p
p
In the next slides you will review:
Line of Best Fit or Regression LineA. When do you use this?B. How does your calculator
help?C. Give a set of sample data in
question format to see if your students can find the regression equation.
Line of best fit or regression
You use to come up with a linear equation that best fits the data.
Put the input in list 1 and the out put in list 2
Then hit stat calc
Next hit 4:linreg(ax=b)
Y=ax+b is the line of best fit for the data
Question
What is the line of best fit for the given data points?
(0,5) (1,9) (-1,4) (-3,0) (-2,1) (3,13)
Y=1.5x+4.8