6th Grade Math Textbook, Fundamentals

Lesson 14-8 for exercise sets. &KDSWHU 

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Solve. Check to justify your answer.

1.z 6 z 10  15 2.6(4  7 x) 2(3  30 x) 3.  12

4.Discuss and Write Your classmate began solving exercise 2 by dividing both

sides by 6. You began by distributing the 6 and the 2 over the expressions

in parentheses. Are both methods correct? Explain why or why not.

10 n 20

20

Some multistep equations require the use of the Distributive Property.

Roxie has 2 fewer bags than her friend Shelly. Callie has

2 more than five times as many bags as Roxie. If Callie

has 17 bags, how many bags does Shelly have?

Let snumber of Shelly’s bags.

number of Roxie’s bags number of Callie’s bags

2 5(s2)  17

Solve: 2 5(s2)  17

2 5(s) 5(2)  17 Apply the Distributive Property

of Multiplication over Subtraction.

2  5 s 10  17 Combine like terms.

5 s 8  17 Simplify.

5 s 8  8  17  8 Add 8 to both sides.

5 s 25 Simplify.

 Divide both sides by 5.

s 5 Simplify.

So Shelly has 5 bags.

Sometimes multistep equations have the variable on both

sides of the equation.

Solve: 50 0.1c 10 0.5c

50 0.1c0.1c 10 0.5c 0.1c

50  10 0.4c Simplify.

50  10  10  10 0.4c

40 0.4c Simplify.

 Divide both sides by 0.4.

100 c Simplify.

So, in the equation 50 0.1c 10 0.5c, the value of cis 100.

0.4c

0.4

40

0.4

Subtract 10 from

both sides.

Subtract 0.1c

from both sides.

25

5

5 s

5

Check: 2 5(s2)  17

2 5(52) 17 Substitute.

2 5(3) 17 Simplify.

2 15 17 Multiply, then add.

17  17 Tr u e

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Check: 50 0.1c 10 0.5c

50 0.1(100) 10 0.5(100)

Substitute 100 for c.

50  10 10  50 Simplify.

60  60 Tr u e

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