Question

Factor: c^2 - d^2
A. (c + d)(c - d)
B. (c + d)(c + d)
C. (c + 2d)(c - d)

Answer 1

A

Answer 2

a

Answer 3

If you are unsure do the multiplication: \[(c+d)(c-d)=c^2-cd+cd-d^2 = c^2-d^2\]

Answer 4

The "difference of two squares" rule is worth remembering, at least until factoring second-degree polynomials becomes second-nature:
\[\Large {a^2} - {b^2} = (a + b)(a - b)\]