Question

x^3 + 64 = 0

Answer 1

x^3 + 64 = 0
x^3 + 4^3 = 0
(x + 4)(x^2 -4x + 16) = 0
I used the fact that (a^3 + b^3) = (a + b)(a^2 -ab + b^2)

Answer 2

Can you carry it on from there?

Answer 3

This one you could also solve by just plugging in numbers for x that look like they might work.

Answer 4

i already had (x + 4)(x^2 -4x + 16) = 0 but i have no idea what to do after that

Answer 5

@BangkokGarrett

Answer 6

When you multiply 2 things together to get 0, one of them must be 0.
So,
x + 4 = 0 or x^2 - 4x + 16 = 0
x = -4

The other one has no real solutions. since (-4)^2 - 4*1*16 is negative

So x = -4 is the only answer