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cmcox
Oct 17, 2011, 07:10 PM
f(x) = x^2 - 12x 36

find a value of x such that f(x)= 9

ebaines
Oct 18, 2011, 05:50 AM
First, I assume that what you meant to write is:
f(x) = x^2 -12x +36

Please confirm.

You know this equals 9, so:


9 = x^2 -12 x +36


Subtract 9 from both sides:


0 = x^2 -12x +27


Now you can factor this and find two solutions for x. Post back with what you get for answers and we'll check it for you.