Given the function below:

To find f(-2), we substitute x = -2 in the equation. Since f(-2) means the value of f(x) at x = -2.

Replace x-term to -2 and evaluate.

Answer
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Answer:
I'd use A = πr^2
The area is 28.3 if we're using 3.14 as pi (rounded to the nearest tenth)
Okay so since we have to put 252 miles per 8 gallons into the simplest form I'm going to say that we divide 252/8=31.5 so we should have 31.5 miles per gallon as our answer