Question

Find the value of k if the points (8, 1)
(k, 4) and (2, 5) are collinear
​

Answer 1

Answer:

k = 7/2 or 3.5

Explanation:

We apply the formula,

x1(y2-y3) + x2(y3-y1) + x3(y1-y2) = 0

8(4-5)+k(5-1)+2(1-4) = 0

8× -1 + k ×4 + 2 × -3 = 0

-8 + 4k -6 =0

4k = 14

k= 14÷4

k= 7 ÷ 2