## Intermediate Algebra for College Students (7th Edition)

$f(x)$ is in the form $f(x)=mx+b$, thus the slope is $m=-0.28$, which means the rate of change of $f(x)$ per unit change of $x$ is $-0.28$. Thus the percentage of US taxpayers audited by the IRS decreases by $0.28$ percent each year.