SOLUTION: What is the value of f(g(9)) if f(x)=4x^2-6 and g(x)=x-3

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Question 1083327: What is the value of f(g(9)) if f(x)=4x^2-6 and g(x)=x-3
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!

Form the composition. Let x be 9. Evaluate.

4%28x-3%29%5E2-6
4%289-3%29%5E2-6
4%286%29%5E2-6
144-6
138

Answer by ikleyn(52795) About Me  (Show Source):
You can put this solution on YOUR website!
.
g(9) = 9 - 3 = 6.

Therefore, f(g(9)) = f(6) = 4*6^2 - 6 = 4*36 - 6 = 144 - 6 = 138.

Writing by "gosgarithmetic" is WRONG.

Simply ignore it, for your safety.