You can put this solution on YOUR website! the rise is the diffence between the y coordinates and the run is the difference between the x coordinates (-2,4)=(x1,y1) (2,-1)=(x2,y2)
:
m=slope = rise/run==(y2-y1)/(x2-x1) or (y1-y2)/(x1-x2)
:
(4-(-1))/(-2-2)=-(5/4)