Page 49 - Math Course 1 (Book 2)

Multi-Step Linear Equations

Step 3: Remove zero pairs Solve Using Multiplication and Addition

Example

s
Solve –9 = –11
12

s
–9 = –11 Original equation
3x = –12 12
Group the tiles to form zero pairs and remove the
zero pairs. s
–9 + 9 = –11 + 9 Add 9 to each side.
12
Step 4: Group the tiles
s
= –2 Simplify.
12

s
12( )= 12(–2) Multiply each side by 12.
12

3x = –12 Answer s = –24 Simplify

Separate the tiles into 3 equals groups to match the
3 x–tiles. Each x tile is paired with 4 negative 1 tiles.
Thus, x = –4

Write and Solve a Multi-Step Equation
Let’s Begin
Example

Solve Using Addition and Division SHOPPING
Susan had a $10 coupon for the purchase of any
Example item. She bought a coat that was its original
1
2
price. After using the coupon, Susan paid $125 for
Solve 5q –13 = 37. Check your solution. the coat before taxes. What was the original price
of the coat? Write an equation for the problem.
5q – 13 = 37 Original equation Then solve the equation.

5q – 13 + 13 = 37 + 13 Add 13 to each side. Words One-half of the price minus ten
dollars is 125.
5q = 50 Simplify.
Variables Let p = the original price.
5q 50
= Divide each side by 5.
5 5 1
Equation p – 10 = 25
2
Answer q = 10 Simplify.

To check, substitute 10 for q in the original equation.

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