Solve the problem using the work backward strategy.

3. A number is divided by 3. Then 5 is added to the quotient. After subtracting 2, the result is 10. What is the number?

4. Dexter and Roshonda shared a pizza. Dexter ate 3 more than twice as many pieces as Roshonda, who ate 3 pieces. If there are 4 pieces left, how many pieces were there initially?

1. A2. B3. C4. D0% 0%0%0%

(over Lesson 3-4)

A. 25

B. 16

C. 18

D. 21

Solve the problem using the work backward strategy.A number is divided by 3. Then 5 is added to the quotient. After subtracting 2, the result is 10. What is the number?

1. A2. B3. C4. D

0% 0%0%0%

(over Lesson 3-4)

A. 16

B. 15

C. 12

D. 8

Dexter and Roshonda shared a pizza. Dexter ate 3 more than twice as many pieces as Roshonda, who ate 3 pieces. If there are 4 pieces left, how many pieces were there initially?

Main Idea and VocabularyExample 1:Solve a Two-Step EquationExample 2:Solve Two-Step EquationsExample 3:Solve Two-Step EquationsExample 4:Solve Two-Step EquationsConcept Summary: Solving Two-Step EquationsExample 5:Real-World Example

• two-step equation – an equations that has 2 operations.

• Solve two-step equations (2.8.8E) (M7.D.2.1)

Solve Two-Step Equations

Solve –3c + 9 = 3. Check your solution.

–3c + 9 = 3 Write the equation.

–3c = –6 Simplify.

c = 2 Simplify.

–9 = –9 Subtract 9 from each side.

Divide each side by –3.

Answer: The solution is 2.

Solve Two-Step Equations

Check

–3c + 9 = 3 Write the original equation.?–3(2) + 9 = 3 Replace c with 2.

3 = 3

–6 + 9 = 3 Simplify.?

1. A2. B3. C4. D0% 0%0%0%

A. –3

B. –1

C. 3

D. 7

Solve –8k + 7 = 31. Check your solution.

PARKS There are 76 thousand acres of state parkland in Georgia. This is 4 thousand acres more than three times the number of acres of state parkland in Mississippi. How many acres of state parkland are there in Mississippi?

Words Three times the number of acres of state parkland in Mississippi plus 4,000 equals 76,000.

Variable Let m = the acres of state parkland in Mississippi.

Equation 3m + 4,000 = 76,000

3m + 4,000 = 76,000 Write the equation.

Answer: There are 24,000 acres of state parkland in Mississippi.

3m = 72,000Simplify.

m = 24,000Simplify.

–4,000 = –4,000Subtract 4,000 from

each side.

Divide each side by 3.

1. A2. B3. C4. D

0% 0%0%0%

A. 16 hits

B. 36 hits

C. 56 hits

D. 72 hits

BASEBALL Mathew had 64 hits during last year’s baseball season. This was 8 less than twice the number of hits Gregory had. How many hits did Gregory have during last year’s baseball season?

End of the Lesson

GUIDED PRACTICE1. Syreeta wants to buy some CDs, each

costing $14, and a DVD that cost $23. She has $65 to spend. Write and solve an equation to find how many CDs she can buy. 14c + 23 = 65

-23 =-23

14c = 42

14 14

c = 3

Five-Minute Check (over Lesson 3–4)

Image Bank

Math Tools

Solving Equations Using Models

Perimeter

Solving Equations Two-Step Equations