Suatu garis melalui titik (1,2) dan (-3,-4),maka persamaan garisnya adalah...

Jawab :

Persamaan garis ; melalui titik (1,2) , dan (-3,-4)

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

y - y1 = m(x - x1)
y - 2 = 3/2(x - 1)
y - 2 = 3/2x - 3/2 x 1
y - 2 = 3/2x - 3/2
--------------------------- x 2
2. y - 2 . 2 = 3/2x . 2 - 3/2 . 2

2y - 4 = 3 - 3
2y - 4 - 3 + 3
2y - 3x + 1 = 0
-3x + 2y + 1 = 0 => ax + by + c = 0