#### Question

In each of the following find the value of '*k*', for which the points are collinear.

(7, -2), (5, 1), (3, -*k*)

#### Solution

For collinear points, area of triangle formed by them is zero.

Therefore, for points (7, -2) (5, 1), and (3, *k*), area = 0

`1/2 [7 { 1- k} + 5(k-(-2)) + 3{(-2) + 1}] = 0`

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

-2*k* + 8 = 0

*k* = 4

Is there an error in this question or solution?

Solution In Each of the Following Find the Value of 'K', for Which the Points Are Collinear. (7, -2), (5, 1), (3, -k) Concept: Area of a Triangle.