Question

is this function linear, quadratic, or exponential?

x	y
5	22.8
6	26.8
7	30.8
8	34.8

linear
quadratic
exponential

Explanation:

Step1: Check x-value differences

The x-values increase by 1 each time: $5-4=1$, $6-5=1$, $7-6=1$, $8-7=1$.

Step2: Check first differences of y-values

Calculate the change in y-values:
$22.8-18.8=4$, $26.8-22.8=4$, $30.8-26.8=4$, $34.8-30.8=4$.

Step3: Classify the function

Since the first differences of y-values are constant (equal to 4), the function is linear.

Answer:

linear