SOLUTION: How do you find all the x-intercepts of the given function: f(x)=(x2-6x)2-22(x2-6x)-135 the "2"'s are squares

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Question 601401: How do you find all the x-intercepts of the given function:
f(x)=(x2-6x)2-22(x2-6x)-135
the "2"'s are squares
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,



Question states***

f(x)= %28x%5E2-6x%29%5E2+-22%28x%5E2-6x%29-135+

Let X = (x^2-6x) 

Then proceeding to find X when f(x) = 0: 

X%5E2+-+22X+-+135+=+0 or (X-27)(X+5) = 0 | X=27 or X= -5

x^2-6x = 27  or x^2-6x-27 = 0  | x = 9 or x = -3

x^2-6x = -5  or x^2-6x + 5 = 0  | x = 5 or x = 1

the x-intercepts of the given function are: -3,1,5,9