Carcass wrote:
If \((x + 1)^2 – 2x > 2(x + 1) + 2\), then x cannot equal which one of the following?
(A) –5
(B) –3
(C) 0
(D) 3
(E) 5
Given: (x + 1)² – 2x > 2(x + 1) + 2
Expand both sides to get: x² + 2x + 1 – 2x > 2x + 2 + 2
Simplify both sides to get: x² + 1 > 2x + 4
Subtract 2x from both sides to get: x² - 2x + 1 > 4
Factor left side to get:
(x - 1)² > 4Now test each answer choice...
(A) –5
If x = -5, we get: (-5 - 1)² > 4
Simplify: (-6)² > 4
Simplify: 36 > 4
Works!!!
(B) –3
If x = –3, we get: (–3 - 1)² > 4
Simplify: (-4)² > 4
Simplify: 16 > 4
Works!!!
(C) 0
If x = 0, we get: (0 - 1)² > 4
Simplify: (-1)² > 4
Simplify: 1 > 4
DOESN'T WORK
Answer: C
Cheers,
Brent