persamaan garis yang melalui titik (-3,-4) dan (-4,-6) adalah

(y-y1)/(y2-y1) = (x-x1)/(x2-x1)
(y-(-4))/(-6-(-4)) = (x-(-3))/(-4-(-3))
(y+4)/ (-2) = (x+3)/(-1)
(-1)(y+4) = (-2)(x+3)
-y -4 = -2x -6
2x - y = -2

semoga membantu