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F(x) = 4x2 - 4x
Find f(-7)

1 Answer

7 votes

The answer would be f(-7) = 224.

To solved you simply plug the -7 in for x. So, it would be f(-7) = 4(-7)^2 - 4(-7).

The first thing you would do is square the 4(-7)^2, to get 4(49) - 4(-7).

Then, multiply these out to the numbers outside the parentheses, to get f(-7) = 196 - (-28).

Remember, negatives cancel out negatives and turn positive, so the equation would actually be f(-7) = 196 + 28.

Simplify this, and you get f(-7) = 224.

User Amit Singh
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