My make an equation in the form y=my+b
You already have the y intercept, -4
Y=mx-4
And you have the two points (1,0) and (0,-4)
To find the slope (rise over run) to get from the two points you go over one up 4
So the slope is 4/1 or 4
The equation is:
Y=4x-4
Hope this helps!
