Question

Determine whether the given points are collinear. 

i. A (0, 2), B (1, -0.5), C (2, -3)

ii. P(1, 2), Q(2, 8/5), R(3, 6/5)

iii L (1, 2), M (5, 3), N (8, 6)

Answer 1

∴ slope of line AB = slope of line BC 

∴ line AB || line BC 

Also, point B is common to both the lines. 

∴ Both lines are the same. 

∴ Points A, B and C are collinear.

∴ slope of line PQ = slope of line QR 

∴ line PQ || line QR 

Also, point Q is common to both the lines. 

∴ Both lines are the same. 

∴ Points P, Q and R are collinear.

∴ slope of line LM ≠ slope of line MN 

∴ Points L, M and N are not collinear.