persamaan garis melalui titik(5,-7) dan (3,-8) adalah

y-y1/y2-y1 = x-x1/x2-x1 =
= y-(-7)/-8-(-7) = x-5/3-5
= y+7/-1 = x-5 /-2
= -2y-14 = -x+5
= -2y+x-14-5
= -2y+x-19 =0