Question

Find the zeros of the function.

f(x) = 9x3 + 18 x2 - 135x

-5 and 3

5 and -3

0, 5, and -3

0, -5, and 3

Answer 1

the answer is
f(x) = 9x3 + 18 x2 - 135x can be written as f(x) = x( 9x2+ 18 x - 135)
the first zero must be = 0
let's find the another zeros by solving 9x2+ 18 x - 135=0
f(-5)=135-135=0, so the answer is

0, -5, and 3

because f(x) = 9x3 + 18 x2 - 135x =x (x+5)(x-3)