tentukan persamaan garis lurus yang melalui titik p(5,-3) dan q(2,-7)

X1 = 5 dan X2 = 2
Y1 = -3. Y2 = -7
m = Y2 - Y 1/X2 - X1
= -7 - (-3) / 2 - 5
= 10 / -3

Jawab :

y2 - y1/ x2 - x1 = (-7) - (-3)/ 2 - 5 = 4/-3 = - 4/3

y - y1 = m(x - x1)
y - (-3) = - 4/3 (x - 5)
y + 3 = - 4/3x + 4/3 x 5
y + 3 = - 4/3x + 20/3
------------------------------- x 3
3 . y + 3 . 3 = - 4/3x . 3 + 20/3 . 3

3y + 9 = -4x + 20
3y + 9 + 4x - 20
3y + 4x - 11 = 0
4x + 3y - 11 = 0 => ax + by + c = 0