Question

write an equation in slope intercept form for the line that passes through the points (3,2) and(-9,6)

Answer 1

Answer:

y = - $\frac{1}{3}$ x + 3

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 ) = (3, 2) and (x₂, y₂ ) = (- 9, 6)

m = $\frac{6-2}{-9-3}$ = $\frac{4}{-12}$ = - $\frac{1}{3}$, hence

y = - $\frac{1}{3}$ x + c ← is the partial equation

To find c substitute either of the 2 points into the partial equation

Using (- 9, 6), then

6 = 3 + c ⇒ c = 6 - 3 = 3

y = - $\frac{1}{3}$ x + 3 ← in slope- intercept form