IMathAS-libretexts

For the linear function $\displaystyle {y}={2}{x}+{5}$ , when $\displaystyle {x}$ increases by 20, how does $\displaystyle {y}$ change?

$\displaystyle {y}$ gets 20 times bigger
$\displaystyle {y}$ increases by 40

$\displaystyle {y}$ increases by 100
$\displaystyle {y}$ increases by 45

It depends on how big $\displaystyle {x}$ is.