Nomor 48,49 caranya gimana ya?

48) (i) 3x-6y-12=0 m = -a/b = -3/-6 = 1/2
(iii) 2x-4y+8=0 m = -2/-4 = 1/2

49) titik yg dilalui (-3,-1) dan (2,-4)
y-y1 x-x1
------ = --------
y2-y1 x2-x1

y+1 x+3
------ = --------
-4+1 2+3

5(y+1) = -3(x+3)
5y+5 = -3x-9
3x+5y+9+5=0
3x+ 5y + 14 =0