### Home > CC4 > Chapter 8 > Lesson 8.2.3 > Problem 8-123

8-123.

If

*f*(*x*) = 3(2), evaluate the expressions in parts (a) through (c) below. Then complete parts (d) and (e).^{x}*8-123 HW eTool*(Desmos). Homework Help ✎*f*(−1)*f*(0)*f*(1)What value of

*x*gives*f*(*x*) = 12?Where does the graph of this function cross the

*x‑*axis? The*y*‑axis? Use this information to sketch the graph.

Substitute −1 for *x* and simplify.

*f*(−1) = 3(2)^{−1}

Refer to part (a).

Refer to part (a).

Substitute 12 for *f*(*x*) and solve for *x*.

*x* = 2

A function crosses the *x*-axis at *y* = 0, and a function crosses the *y*-axis at *x* = 0.

Use the eTool below to find the value of each expression in parts (a) through (c).

Click on the link at right for the full eTool version: Int1 8-123 HW eTool.