SOLUTION: A function f is given by f(4x-1) = 4x2+5. Evaluate f(15). Answer: f(15) = Answer 905

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Question 1120615: A function f is given by f(4x-1) = 4x2+5. Evaluate f(15).
Answer: f(15) = Answer
905
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


905 would be the answer if the function were defined as f(x) = 4x^2+5:

f(15) = 4(15^2)+5 = 4(225)+5 = 900+5 = 905

But the function is defined as f(4x-1) = 4x^2+5. To evaluate f(15), you need to determine the value of x that makes 4x-1 equal to 15.

4x-1 = 15
4x = 16
x = 4

THAT is the value you need to substitute into the expression 4x^2+5 to get the answer.