Find an equation of the line that contains (-3,0) with the slope -4

Question

Find an equation of the line that contains (-3,0) with the slope -4

Answer 1

We have our basic line: f(x) = y

Since our slope is -4, that means that every time x increases, we drop another four points, so we get:

-4f(x) = y

 

When the line crosses the x-axis (or y is at 0), it strikes at the -3 point on the graph, so we have to adjust our x point by three:

-4f(x-3) = y

Answer 2

Hi Dill,

Use the point-slope form for the equation of a line:

y-y₁= m(x-x₁)

m=-4     x₁=-3     y₁=0

 

y-0 =-4(x+3)

y = -4x-12