A line passes through the points (
–
8,9) and (
–
2,
–
9). Write its equation in slope-intercept form.
Write your answer using integers, proper fractions, and improper fractions in simplest form.
First, find the slope using the formula:
m = (y2 - y1) / (x2 - x1)
m = (-9 - 9) / (-2 - (-8))
m = (-18) / (6)
m = -3
Next, use one of the points to find the y-intercept.
I will use (-8,9):
y = mx + b
9 = (-3)(-8) + b
9 = 24 + b
b = -15
Therefore, the equation of the line in slope-intercept form is:
y = -3x - 15