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F(x) = -x^2 - 10x - 13, find f(-2)

User Arina
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1 Answer

23 votes
23 votes

Answer: f(-2) = 11

Concept:

Here, we need to understand the idea of evaluation.

When encountering questions that gave you an expression with variables, then stated: "If x = a, y = b, z = c" (a, b, c are all constants), this means you should substitute the value given for each variable back to the expression.

Solve:

Given information

f (-2) or x = -2

Given function

f(x) = -x² - 10x - 13

Substitute values into the function

f(-2) = -(-2)² - 10 (-2) - 13

Simplify exponents

f(-2) = -(4) - 10 (-2) - 13

Simplify by multiplication

f(-2) = 4 + 20 - 13

Simplify by addition/subtraction

f(-2) = 24 - 13

f(-2) =
\boxed{11}

Hope this helps!! :)

Please let me know if you have any questions

User Christian Lescuyer
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