Question

A line passes through the point (2,-2) and has a slope of -9 . Write an equation in slope-intercept form for this line.

Answer 1

So let’s use the slope-intercept form y=mx+b, since we know the slope, we can plug that in. We get y=-9x+b. Now to find b, let’s plug in 2,-2. We get -2=-18+b. So b=16.

So the equation is y=-9x+16.

Answer 2

Slope-intercept form:

y = mx + b

"m" is the slope, "b" is the y-intercept (the y value when x = 0)

Since you know m = -9, you can plug it in

y = -9x + b

To find "b", plug in the point (2,-2) into the equation

y = -9x + b

-2 = -9(2) + b

-2 = -18 + b  Add 18 on both sides

16 = b

y = -9x + 16