Question

Persamaan garis lurus yg melalui titik A (5, -2) dan tegak lurus dg garis x + 4y = 7 adalah...

Answer 1

M1 = -1/4
m2 = -1/4/-1
       = 1/4
y -y1 = m2 (u-u1)
y - (-2) = 1/4 (u-5)
y + 2 = 1/4 u - 5/4
   y  = 1/4u - 5/4 -2
   y = 1/4u - 3 1/4

Answer 2

4y = - x + 7
  y = (- 1/4)x + 7/4
m₁ = - 1/4
m₁ . m₂ = - 1
- 1/4 . m₂ = - 1
m₂ = 4 (gradien tegak lurusnya)

Persamaan garis:
y - b = m(x - a)
y - (- 2) = 4(x - 5)
y + 2 = 4x - 20
4x - y - 22 = 0