Page 118 Reasoning Strategy: Write an equation

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Page 118 Reasoning Strategy Write an equation

• Write an equation to solve a problem

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Example

• Writing equations A moving van rents for 29.95 a
  day plus .12 per mile. Mr. Reynolds bill was
  137.80, and he drove the van 150 mi. For how
  many days did he have the van?
• 1. What is the goal of this problem?
• 2. How many miles did Reynolds Drive?
• 3. What does the cost without mileage?
• 4. What is the mileage charge?

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Make and carry out a plan

• Write an equation

Words
29.95
.12/mi
150 mi 137.80
Number of days
?

?
d the number of days
Equation
4
Solve
29.95
0.12
150 137.80
d
?

?
5
Check answer

• 29.95 30
• 0.12 0.1
• 137.80 140

30
0.1
150 140
4
?

?
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CA Standards Check

• Suppose that Mr. Reynolds bill was 161.80 and
  drove the van 350 mi.
• a. How would the equation change?
• b. Solve the new equation to find how many days
  he rented the van.
• c. Estimate to check your answer.

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CA Standards Check

• 2. Mr. Reynolds rented the van for one day. His
  bill was 41.95. How many miles did he drive?

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Homework

• Page 360 2, 4, 5, 8,