Slope-intercept form:
y = mx + b
"m" is the slope, "b" is the y-intercept (the y value when x = 0) or (0,y)
To find "m", you can use the slope formula and plug in the two points:
(2,3) = (x₁ , y₁)
(0,9) = (x₂ , y₂)
[tex]m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]
[tex]m=\frac{9-3}{0-2}[/tex]
[tex]m=\frac{6}{-2}[/tex]
m = -3
y = -3x + b
To find "b", you can plug in one of the points into the equation (however they already gave you the y-intercept (0,9) or 9)
(2,3)
y = -3x + b
3 = -3(2) + b
3 = -6 + b
9 = b
y = -3x + 9
