Core Connections Geometry, 2013
CC
Core Connections Geometry, 2013 View details
1. Section 1.1
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Exercise 45 Page 27

Practice makes perfect
a To solve an equation, we should first gather all of the variable terms on one side of the equation and all of the constant terms on the other side by using the Properties of Equality.

75=14y+5
70=14y
14y=70
y=5

The solution to the equation is y=5. We can check our solution by substituting it into the original equation.

75 = 14y+5
75 ? = 14( 5)+5
â–¼
Simplify
75 ? = 70+5
75=75 ✓

Since the left-hand side is equal to the right-hand side, our solution is correct.

b To solve an equation, we should first gather all of the variable terms on one side of the equation and all of the constant terms on the other side by using the Properties of Equality.

- 7r+13=- 71
- 7r = - 84
- 7r/- 7=- 84/- 7
7r/7=84/7
r=12

The solution to the equation is r=12. We can check our solution by substituting it into the original equation.

- 7r+13=- 71
- 7( 12)+13 ? = - 71
â–¼
Simplify
- 84 +13 ? = - 71
- 71 = - 71 ✓

Since the left-hand side is equal to the right-hand side, our solution is correct.

c To solve an equation, we should first gather all of the variable terms on one side of the equation and all of the constant terms on the other side by using the Properties of Equality.

3a+11=7a-13
3a+24=7a
24=4a
4a=24
a=6

The solution to the equation is a=6. We can check our solution by substituting it into the original equation.

3a+11=7a-13
3( 6)+11 ? = 7( 6)-13
â–¼
Simplify
18+11 ? = 42-13
29=29 ✓

Since the left-hand side is equal to the right-hand side, our solution is correct.

d To solve an equation, we should first gather all of the variable terms on one side of the equation and all of the constant terms on the other side by using the Properties of Equality.

2m+m-8=7
3m-8=7
3m=15
m=5

The solution to the equation is m=5. We can check our solution by substituting it into the original equation.

2m+m-8=7
2( 5)+ 5-8 ? = 7
â–¼
Simplify
10+5-8 ? = 7
7=7 ✓

Since the left-hand side is equal to the right-hand side, our solution is correct.