diketahui titik A(-1,-8,x), B(2,y,4) dan C(3,-4,6) segaris. nilai x dan y masing masing adalah...

AB = k. BC
b-a  = k (c- b)
(2, y, 4) - (-1, -8, x) = k. ((3, -4, 6) - (2, y, 4))
(3, y + 8, 4 - x) = k (1 , -4-y, 2)
cari dl nilai k
3 = k
k = 3
nilai y
y + 8 = 3(-4-y)
y + 8 = -12 - 3y
4y = -12 - 8
4y = -20
  y = -5
nilai x
4 - x = 3 . 2
4 - x = 6
4 - 6 = x
x = -2