Question

What is the factored form of the expression 144x2 - 49?

A. (12x - 7) (12x + 7)

B. (12x - 7) (12x - 7)

C. (144x + 1)(x - 49)

D. (144x - 1) (x + 49)

Answer 1

A

Explanation:

Difference of squares: (a^2 - b^2) = (a - b)(a + b)

(144x^2 - 49) = (12x - 7) (12x + 7)

Answer 2

A. (12x - 7) (12x + 7)

Explanation:

144x^2 - 49

Rewriting

(12x)^2 - 7^2

Recognizing this is the difference of squares

a^2 - b^2 = ( a-b) (a+b)

( 12x-7) (12x+7)