Question

Find the zeros of the function.f(x) = 9 x^3 - 72 x^2 + 135x

A . -5 and -3

B. 0, -5, and -3

C. 5 and 3

D. 0, 5, and 3

Answer 1

help please :)

Answer 2

Start by pulling out a 3x from each term, leaving you with 3x^2-24x+45. Should make it easier.

Answer 3

I think its either C or D

Answer 4

It can't be C. There are two factors of 3x^2-24x+45. Also, the 3x that you pulled out would give you another solution for x. So there has to be 3 answers.

Answer 5

So either C or D, which is it?
the -5 or +5 is throwing me off

Answer 6

I just said it can't be C.

Answer 7

i meant B or D

Answer 8

It's D.

Answer 9

Thank you :)

Answer 10

You could try to factor it. I suck at this, so I usually end up using the quadratic formula. You'll use that a lot in math, so it'd be good to practice it.