Question 279523
sol:
slope of the line passing through the points (x1,y1) and (x2,y2) is 
(y2-y1)/(x2-x1)
slope of the line passing through the points (7,-5) (-1,8)
here x1=7,y1=-5,x2=-1,y2=8
slope=(y2-y1)/(x2-x1)
slope=(8-(-5))/(-1-7)
slope=(8+5)/(-8)
slope=13/(-8)
slope= - 13/8