Question

find the value of k for which the points are collinear(7,-2)(5,3)(3,k)​

Answer 1

Answer:

Step-by-step explanation:

If the points are collinear then the area of triangle will be O.

Δ=  1/2 ∣ x  1 ​ ( y  2 ​  − y  3   ) + x  2 ​ ( y  3  − y  1 ​  ) + x  3 ​  ( y  1 ​  − y  2 ​ ) ∣

1 / 2 ∣  7 ( 3 − k ) + 5 ( k + 2 ) + 3 ( −2 −3 ) ∣ = 0

∣ 21 − 7k + 5k + 10 − 15 ∣ = 0  

∣ −2k - 16 ∣ = 0

-2k = 16  

so  k = -8