Question

Which equation has solution x = -3?

A) 2x - 7 = -1
B) 3x + 8 = 1
C) 1/2x + 8 = 10
D) 1/2 (2x - 6) = -6

Answer 1

A) 2x - 7 = -1

Add 7 to both sides of the equation.

2x = 6

x = 3

Choice A is not the answer.


B) 3x + 8 = 1

Subtract 8 from both sides.

3x = -7

Divide both sides by 3.

x = -2.3 repeating

Choice B is not the answer.

C) 1/2x + 8 = 10

1/2x = 2

Divide both sides by 1/2.

x = 4

Choice C is not the answer.

By process of elimination, choice D is the answer.

D) 1/2(2x - 6) = -6

x - 3 = -6

Add 3 to both sides.

x = -3