Question

Not quite sure on this problem???


Which of the following is a factor of 512x3 - 125?

Answer choices:

8x + 5

64x2 + 80x + 25

64x2 + 40x + 25

None of the above

Answer 1

I think it's D

Answer 2

512x3 - 125 is the difference between 2 perfect cubes and can be rewritten as (8x)^3 - 5^3. The difference between 2 perfect cubes can be factored as follows: a^3 - b^3 = (a - b)(a^2 + ab + b^2). Your "a" is 8x and your "b" is 5.

Answer 3

So, you do have a factor in one of the choices. Hint: it has 3 terms in it, so it's one of either B or C.

Answer 4

C

Answer 5

It'd be +40x....right?

Answer 6

"C" is correct! You got it! Good job! The answer is indeed 64x2 + 40x + 25

Answer 7

Thank you!!!!! You're such a help!!!!!!!!!!!!!!!!!!!!!!!!