tentukan gradien garis yang melalui titik (1,5) dan (6,2)

persamaan garis :
(y-y1)/(y2-y1) = (x-x1)/(x2-x1)
(y-5)/(2-5) = (x-1)/(6-1)
(y-5)/(-3) = (x-1)/5
5(y-5) = (-3)(x-1)
5y - 25 = -3x + 3
3x + 5y = 28

gradien
= (x2-x1)/(y2-y1)
= (2-5)/(6-1)
= -3/5