## College Algebra (10th Edition)

The average rate of change is $3$ units.
RECALL: The average rate of change of a function from $x=a$ to $x=b$, where $a \gt b$, is given by the formula: $\text{average rate of change} = \dfrac{f(b) - f(a)}{b-a}$ Use the formula above to obtain: $\text{average rate of change}$ $\\= \dfrac{f(b) - f(a)}{b-a} \\=\dfrac{f(4)-f(0)}{4-0} \\=\dfrac{(3\cdot 4 - 5) - (3 \cdot 0 - 5)}{4} \\=\dfrac{7-(-5)}{4} \\=\dfrac{7+5}{4} \\=\dfrac{12}{4} \\=3$