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Evaluating Expression 1
Evaluating Expression
1
Warm Up
Agenda2
OBJECTIVE: SWBAT evaluate algebraic expressions. Language Objective: SWBAT describe the steps to evaluating expressions.
A magic store is selling exploding pens for $3 each plus $1 for tax.
Do you agree or disagree? Explain.
3101
Kyle thinks you can figure out the cost of 10 pens with the below.numerical expression
Quick Discussion:Algebraic Expression?
3p+1Click to reveal next part
Launch- Shopping with Marvin
Agenda3
Marvin the Math Magician has a problem for you.
How much will Marvin have to pay for 12 wands and 7 hats?
He wants to buy some magic wands
and some magician hats.
The wands cost $8 each and $5 for each hat.
Agenda4
How much will Marvin have to pay for 12 wands and 7 hats?
The wands cost $8 each and $5 for each hat.
How did you get your answer?
How can we write a to show our answer of 131?
numerical expression
81257Click to reveal next part
Launch- Shopping with Marvin
Explore 1- Evaluating with Marvin
Agenda5
How much will Marvin have to pay for 6 wands and 3 hats?
Remember: the wands cost $8 each and $5 for each hat.
Click to reveal next part
Write an numerical expression to find the answer.
8653
4815
63
Agenda6
What changed in the two examples?
8w+5h
Sometimes it helps to represent a problem as an algebraic expression.
Numerical ExpressionThe wands cost $8 each and $5 for each hat.
w= # of wandsh= # of hats
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12 wands7 hats
6 wands3 hats
8
512 7
8
56 312 76 3
Explore 1- Evaluating with Marvin
Agenda7
AlgebraicExpression
8w 5h
8
510 2
80
10
90
w hThis is called substitution!!
Click to reveal next part
We just evaluated the expression.
evaluate
w = 10 h = 2
How much will Marvin have to pay for 10 wands and 2 hats?
Explore 1- Evaluating with Marvin
Agenda8
AlgebraicExpression
w = 10 h = 2
How much will Marvin have to pay for 10 wands and 2 hats?
8w 5h
8
510 2
80
10
90
This is called substitution!!
Click to reveal next part
We just evaluated the expression.
Evaluate: to calculate the value of a numerical or algebraic expression.
evaluate
Explore 1- Evaluating with Marvin
Agenda9
w=h=
8w 5h
8
59 7
72
35
107
w h
Find the cost of buying 9 wands and 7 hats.
Steps:1. Copy the expression. 2. Substitute the value in for the variable.3. Evaluate using the order of operations.
Click to reveal next part
97
Explore 1- Evaluating with Marvin
Explore 2- Formulas
Agenda10
Flashback…
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Objective: evaluate algebraic expressions.
For example: engineers, architects and builders use geometric formulas every day.
C dCircumference
V lwh
Volume Rectangular Prism
SA 2r2 dh
Surface AreaCylinder
We can use the process of evaluating to solve problems in the real world.
Explore 2- Formulas
Agenda11
Volume is the amount of space a shape takes up. The expression for calculating the volume of the rectangular prism is below.
Find the volume 9ft 4ft
5ft
lwh
365
180 ft 3
l
w
h59
4
Click to reveal next part
Steps:1. Copy the expression.
2. Substitute the value in for the variable.3. Evaluate using the order of operations.
lwh or
9ft 4ft
5ft
Agenda12
Surface Area is the total of the area of all sides. The expression for calculating the surface area of a rectangular prism is below.
Find the volume.
2lw 2lh 2wh
Click to reveal next part
Steps:1. Copy the expression.
2. Substitute the value in for the variable.3. Evaluate using the order of operations.
2lw
2lh
2wh9
4
2 59
2 4 5
2
72
90
40
202 ft 2
Explore 2- Formulas
Exit Slip
Agenda13
Kiara was asked to evaluate the expression . Her answer was 14.
27 p
Did she substitute 11, 13, or 15? How do you know?
Answer : 1327 – 13
14
