Answer:
y = - 3x + 9
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (2, 3) and (x₂, y₂ ) = (- 1, 12)
m = [tex]\frac{12-3}{-1-2}[/tex] = [tex]\frac{9}{-3}[/tex] = - 3, thus
y = - 3x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (2, 3), then
3 = - 6 + c ⇒ c = 3 + 6 = 9
y = - 3x + 9 ← equation of line
