Five-Minute Check (over Lesson 5–7)

Main Idea and Vocabulary

Example 1:Addition Equations

Example 2:Subtraction Equations

Example 3:Write and Solve Equations

• I will write and solve addition and subtraction equations.

• defining the variable

Addition Equations

x + 8 = 15

Solve x + 8 = 15.

7 + 8 = 15

Answer: So, x = 7. The solution is 7.

You know that 7 + 8 is equal to 15.

1. A

2. B

3. C

4. D0% 0%0%0%

A. 4

B. 5

C. 9

D. 15

Solve x + 5 = 9.

Subtraction Equations

Solve 7 – x = 4.

7 – x = 4 Write the equation.

THINK 7 minus what number is equal to 4?

7 – 3 = 4 You know that 7 minus 3 is 4.

Answer: So, x = 3. The solution is 3.

1. A

2. B

3. C

4. D0% 0%0%0%

A. 3

B. 4

C. 5

D. 6

Solve 10 – x = 6.

Write and Solve Equations

Tim bought a book and a magazine at the bookstore. He spent $9. If a magazine costs $3, how much did the book cost?

Words

Variable

Expression

Cost of the book plus cost of the magazine is $9.

Let b represent the cost of the book.

b + 3 = 9

Write and Solve Equations

b + 3 = 9 Write the equation.

THINK What number plus 3 is equal to 9?

6 + 3 = 9 Replace b with 6 to make the equation true.

Answer: So, b = 6. The cost of the book is $6.

To check your solution, replace the variable with 6. Does this make the right side of the equation equal to the left side?

Check b + 3 = 9 Write the equation.

Replace b with 6.

9 = 9 Simplify. The solution is correct.

6 + 3 = 9?

Write and Solve Equations

1. A

2. B

3. C

4. D0% 0%0%0%

A. $2

B. $3

C. $4

D. $5

Marie bought a candy bar and a soda at the store. She spent $5. If the candy bar cost $2, how much did the soda cost?

End of the Lesson

Five-Minute Check (over Lesson 5–7)

Image Bank

Math Tool Chest

Model Multiplication Equations

1. A

2. B

3. C

4. D0% 0%0%0%

(over Lesson 5–7)

A. 14

B. 1

C. 52

D. 2

Evaluate the expression.

13 – (6 × 2)

1. A

2. B

3. C

4. D0% 0%0%0%

(over Lesson 5–7)

A. 2

B. 7

C. 3

D. 8

Evaluate the expression.

6 + (6 ÷ 3)

1. A

2. B

3. C

4. D0% 0%0%0%

(over Lesson 5–7)

A. 4

B. 3

C. 2

D. 12

Evaluate the expression.

(6 + 6) ÷ 3

1. A

2. B

3. C

4. D0% 0%0%0%

(over Lesson 5–7)

A. 2

B. 4

C. 6

D. 18

Evaluate the expression.

(8 ÷ 4) × 3

1. A

2. B

3. C

4. D0% 0%0%0%

(over Lesson 5–7)

A. 4.3

B. 7

C. 2

D. 8

Evaluate the expression.

(8 ÷ 2) + (9 ÷ 3)