The slop-intercept form:
[tex]y=mx+b[/tex]
m - slope
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
b - y-intercept
We have (0, 2) and (4, -1).
Substitute:
[tex]m=\dfrac{-1-2}{4-0}=\dfrac{-3}{4}=-\dfrac{3}{4}[/tex]
(0, 2) → y = 2 is y-intercept. Therefore b = 2.
Answer: [tex]y=-\dfrac{3}{4}x+2[/tex]