Answer:
y = - 3x + 7
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 =

with (x₁, y₁ ) = (2, 1) and (x₂, y₂ ) = (5, - 8)
m =
=
= - 3 , thus
y = - 3x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (2, 1) , then
1 = - 6 + c ⇒ c = 1 + 6 = 7
y = - 3x + 7 ← equation of line