Which of the following show the factored equivalent of f (x) = (x^2-81) (x+5) and it's zeroes

f (x) = (x²-81) (x+5)

we can write 81 as 9²

f (x) = (x²-9²) (x+5)

using the formula a²-b² = (a+b) (a-b)

factored form is:

f (x) = (x+9) (x-9) (x+5)

to find the zeros, f (x) = 0 and solve for x

0 = (x+9) (x-9) (x+5)

x+9=0, x=-9

x-9=0, x=9

x+5=0, x=-5

zeros are 9, - 9 and 5