Please help me thank you

Answer:
Step-by-step explanation:
Put the value where the variable is and do the arithmetic.
Personally, I find it easier not to deal with so many minus signs. I would rewrite the function to ...
f(x) = -(8 +x)
I find it easier to evaluate the series of argument values when they are in increasing order. This serves as a check, because we expect the function values to be in decreasing order.
f({-3, -2, 0, 2, 4}) = -(8 +{-3, -2, 0, 2, 4}) = -{5, 6, 8, 10, 12} = {-5, -6, -8, -10, -12}
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As always, for repetitive evaluation of the same function, a spreadsheet or graphing calculator is a handy tool.