# If f(x) = 4x + 12 and g(x) = 3 - x^2, find f(8), g(3), and f(-4).

## Question:

If *f*(*x*) = 4*x* + 12 and *g*(*x*) = 3 - *x*2, find *f*(8), *g*(3), and *f*(-4).

## Evaluating Functions:

In mathematics, we represent a function algebraically using function notation, *f*(*x*). That is, we set *f*(*x*) equal to an algebraic expression in *x*. If we are given a function, *f*(*x*), in function notation, and asked to evaluate *f*(*a*), for some number *a*, we do so by plugging *a* in for *x* in the algebraic expression and simplifying.

## Answer and Explanation:

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View this answerIf *f*(*x*) = 4*x* + 12 and *g*(*x*) = 3 - *x*2, then *f*(8) = 44, *g*(3) = -6, and *f*(-4) = -4.

Let's start by finding *f*(8). We are given that *f*(*x*) = 4*x* + 12, so to...

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Chapter 1 / Lesson 8Function notation is a mathematical concept that deals with displaying a system of symbols. Discover the definition and examples of function notation, as well as how to write it, how to evaluate functions, and how to combine two functions in function composition.