If x2 + mx + m is a perfect-square trinomial, which equation must be true?

Question

A.x² + mx + m = (x – 1)²

Bx.² + mx + m = (x + 1)²

C.x² + mx + m = (x + 2)²

D.x² + mx + m = (x + 4)²

Answer 1

According to the problem, the coefficient of the x term and the constant term must be equal. The only choice for which that holds is C because (x + 2)² = x² + 4x + 4.