Answer: 24
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Work Shown:
f(x) = x^2 - 2x
f(2) = 2^2 - 2*2 ... replace every x with 2
f(2) = 4 - 4
f(2) = 0
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g(x) = 12-8x
g(3) = 12-8*3 ... replace every x with 3
g(3) = 12-24
g(3) = -24
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Subtract the results of the previous two sections
f(2) - g(3) = 0 - (-24)
f(2) - g(3) = 0 + 24
f(2) - g(3) = 24