ax+b=y
put both values first put the first point and then the second point the left point for x and the right point for y
you will get
(5,-17) 5a+b=-17
(8,-29) 8a+b=-29
subtract both of the equations
you will get -3a=12 so a is -4
put a in any equation that we found
5(-4)+b=-17
-20+b=-17
b is 3
so the equation is -4x+3=y
