7th Grade Math

Chapter Study Guide and Review

Multiplication and

Division Equations

Solve One-Step Multiplication and Division Equations (Lesson 2B)

Solve each equation. Check your solution.

25. 7 c = 28 26. - 8 w = 72


26. 10 y = - 90 28. - 12 r = - 36


27. _ 3 a = 4 30. _x 9 = 6


28. MONEY Matt borrowed $98 from his
    father. He plans to repay his father at $14
    per week. Write and solve an equation to
    find the number of weeks w required to
    pay back his father.

EXAMPLE 5 Solve - 4 b = 32.

• 4 b = 32
  _-^4 b
  
  
  • 4
    = _^32
    
    
    • 4
      Division Property of Equality
      b = - 8
    
    
    
    
  
  
  
  

EXAMPLE 6 Solve _b

7

= - 6.

_b

7

= - 6

_b

7

· 7 = - 6 · 7 Multiplication Property of Equality

b = - 42

Solve Equations with Rational Coefficients (Lesson 2D)

Solve each equation. Check your solution.

32. -3.4 = 1.7d 33. 0.5x = 0.75


33. 0.42y = 1.26 35. 1.5t = 30


34. ^45 r = 1 37. - 2 = ^25 m


35. BLIMP A blimp travels 300 miles in
    7.5 hours. Assuming the blimp travels
    at a constant speed, write and solve an
    equation to find the speed of the blimp.
    Use the formula d = rt.

EXAMPLE 7 Solve 2.5r = 30.

2.5r = 30

_2.5r

2.5

= _^30

2.5

Division Property of Equality

r = 12

EXAMPLE 8 Solve - 4 = _^2

3

s.

• 4 = _^2
  3
  s

(

_^3

2 )^ -4 =(

_^3

2 )^

_^2

3 s^ Multiplication Property of Equality

• 6 = s

Lesson 2

256 Equations and Inequalities

Multi-Step Equations

Solve Two-Step Equations (Lesson 3B)

Solve each equation. Check your solution.

39. 3 y - 12 = 6 40. 6 x - 4 = 20


40. 2 x + 5 = 3 42. _^35 m + 6 = - 4


41. DVDS Blake had 6 times the amount
    of DVDs that Daniel had. Blake just
    bought 5 more. Write and solve an
    equation to find how many DVDs
    Daniel had if Blake now has 155.

EXAMPLE 9 Solve 3p - 4 = 8.

3 p - 4 = 8

+ 4 = + 4 Addition Property of Equality

3 p = 12

3 p

3 = (^123) Division Property of Equality
p = 4
Lesson 3
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