If the points A(7, -2), B(5, 1) and C(3, k) are collinear, then find the value of k.

Asked by Topperlearning User | 24th Nov, 2013, 05:21: AM

Expert Answer:

If the points A, B and C are collinear, then the area of triangle ABC = 0.

[7(1-k)+5(k+2)+3(-2-1)] = 0

7-7k+5k+10-9=0

-2k+8=0

k=4

Thus, the points are collinear for k=4.

Answered by  | 24th Nov, 2013, 07:21: AM