Question

Consider the function f defined by:f(x)=4x-12 FIND: The value of f at x=-7The value of f when x=1

Answer 1

• f(-7)=-40

,

• f(1)=-8

Explanation:

Given the function f(x) defined below:

`f(x)=4x-12`

(a)The value of f at x=-7

When x=-7

Substitute -7 for x:

`\begin{gathered} f(-7)=4(-7)-12 \\ =-28-12 \\ =-40 \end{gathered}`

The value of f at x=-7 is -40.

(b)The value of f when x=1

When x=1

Substitute 1 for x:

`\begin{gathered} f(1)=4(1)-12 \\ =4-12 \\ =-8 \end{gathered}`

The value of f at x=1 is -8.