slope = rise over run = the change in y over the change of x
if you want it to be exactly 2, then you have to make sure the equations are proportional.
-5 - y / 6-1
so you simplify it -5-y/ 5
the answer needs to be 2 times 5,
2 x 5 = 10, so you need to add 5 because that's what you subtract from it in the end.
y = 15
