persamaan garis yang melalui titik (1 -2)) tegak lurus garis 4x + 3y + 7 = 0

(1, -2) -> x1 = 1, y1 = -2
4x + 3y + 7 = 0
3y = -4x - 7
y = -4x/3 - 7/3
maka m1 = -4/3
karena yang diketahui tegak lurus
maka m1 × m2 = -1
m1 × m2 = -1
-4/3 × m2 = -1
m2 = 3/4

pers garis:
y - y1 = m2 ( x - x1 )
y - (-2) = 3/4 ( x - 1)
y + 2 = 3/4 ( x - 1)
4y + 8 = 3x - 3
0 = 3x - 4y - 11