6th Grade Math Textbook, Progress

Complete each step to solve and check each equation.

1. w
   
   9 
   51 2. f
   14  8
   w
   
   9  
   51  f
   14
    8
   
   w  f

Check: 

 9 

 51 Check: 
 14 
 8


 51  8

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Addition and Subtraction

Equations with Integers

14-2

From 9:00 P.M. to 6:00 A.M., the temperature rose

7 degrees Celsius. At 6:00 A.M., it was 2°C. What

was the temperature at 9:00 P.M.?

To find the temperature at 9:00 P.M., write and solve an equation.

Let trepresent the temperature at 9:00 P.M.

t

 7 
 2

t

 7 
 7 
 2 
 7

t 5

Check: 5 

 7 

 2


 2 
 2 True

The temperature at 9:00 P.M. was 5°C.

Study these examples.

Solve: n
 16  40

n
 16 

 16  40 

 16

n 24

Check:  24 
 16 
 40

 40  40 True

temperature rise in temperature

at 9:00 P.M. plus temperature equals at 6:00 A.M.

t 
 
 7  
 2

Subract 
7 from both sides.

solution

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 Substitute 5 for t.

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Remember:

Adding or subtracting the

same amount from both

sides of a true equation

results in a true statement.

Solve: h
 11 
 4  9

h
 11 
 4  9

h
 15  9

h
 15  15  9  15

h
 6

Check: 
 6 
 11 
 4 
 9

 9  9 True

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