Question

Juan recently entered into a contract for a cell phone plan. The table shows the monthly cost in dollars, f(x), if Juan sends x text messages.

What type of function is represented?

linear
quadratic
logarithmic
exponential

Answer 1

A linear function is represented

Explanation:

The table is:

x f(x)

0 10.00

1 10.02

2 10.04

3 10.06

4 10.08

5 10.10

If we compute the difference between two consecutive function values and we divide it by the difference between their associated x values we get:

(10.02 - 10.00)/(1-0) = 0.02

(10.04 - 10.02)/(2-1) = 0.02

(10.06 - 10.04)/(3-2) = 0.02

(10.08 - 10.06)/(4-3) = 0.02

(10.10 - 10.08)/(5-4) = 0.02

This constant result indicates that a linear function is represented.