Question

Which is a factor of 45x^4−5x^2? Show work.


a. 5x+2 b. 9x−1 c. 6x+5 d. 3x−1

Answer 1

d. 3x - 1.

Explanation:

45x^4−5x^2

The GCF is 5x^2 so we have:

5x^2(9x^2 - 1)

The expression in the parentheses is the difference of 2 squares so:

= 5x^2(3x - 1)(3x + 1)