Question

Which expression makes the equation true for all values of x?

16x - 16 = 4( ? )

A 4x - 4
B 4x - 16
C 2x - 2
D 12x - 12

Answer 1

The answer is B
4x16 - 16 = 48
16x4-16=48

Answer 2

A since if we multiply 4 × 4x, we get 16x, and 4 × 4, we get 16, which cancels with the other 16x - 16 on the left side. That makes sure that any x we choose will cancel out in the end.

Explanation:

1. 16x - 16 = 4(4x-4)

2. 16x - 16 = 16x - 16

3. 0 = 0