Answer: -10
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Work Shown:
First we need to evaluate f(3)
f(x) = -x^2 + 2x
f(x) = -(x)^2 + 2(x)
f(3) = -(3)^2 + 2(3) ... replace every x with 3; apply PEMDAS to simplify
f(3) = -9 + 6
f(3) = -3
Then we subtract 7 from both sides
f(3) - 7 = -3 - 7
f(3) - 7 = -10
