In the $xy$-plane, the graph of $y=f(x)$ is a line that passes throug…

Question

Prompt

In the

x y

-plane, the graph of

y = f (x)

is a line that passes through

(0, 21)

and has a slope of

4

. Which equation defines

f

f (x) = 21 x

f (x) = 21 x + 4

f (x) = 4 x

f (x) = 4 x + 21