Question

Factor Completely: 25x2 - 64 A) 5(x - 8)(x + 8) B) 5(x - 8)(x - 8) C) (5x - 8)(5x + 8) D) (25x - 1)(x + 64)

Answer 1

Rewrite it in the form a^2 - b^2, where a = 5x and b = 8

(5x)^2 - 8^2

Use the Difference of Squares; a^2 - b^2 = (a + b)(a - b)

= C. (5x - 8)(5x + 8)