Question

Which of the following show the factored equivalent of f(x) = (x2 - 81)(x + 5) and its zeroes. f(x) = (x - 6)(x + 6)(x + 5); x= 6, -6, -5 f(x) = (x - 9)(x + 9)(x + 5); x= 9, -9, -5 f(x) = (x - 9)(x + 9)(x + 5); x= -9, -9, -5 f(x) = (x - 6)(x + 6)(x + 5); x= -6, 6, -5

Answer 1

The correct answer is:  [B]:
________________________________________________________
  f(x) = (x - 9)(x + 9)(x + 5);   x= 9, -9, -5 .
________________________________________________________

Answer 2

Answer:

Option B

Step-by-step explanation:

We have to write the function f(x) in the factored form.

f(x) = ( x² - 81 ) ( x+5 )

Since [ a² - b² = ( a-b ) ( a+b) ]

so f(x) = ( x² - 9² ) ( x + 5 )

=  ( x - 9 ) ( x + 9 ) ( x + 5 )

If these factors are the zero factors then

( x - 9 ) = 0 ⇒ x = 9

( x + 9 ) = 0 ⇒ x = -9

x + 5 = 0 ⇒ x = -5

Option B will be the answer.