(Q24) Find the value of 'K' for which the points are collinear (8,1) , (k,-4) , (2,-5).
Given : A(8,1) , B(k,-4) and C(2,-5) are collinear
Area of ∆ABC = 0.
=
1
2
|x
1
(y
2
-y
3
)+x
2
(y
3
-y
1
)+x
3
(y
1
-y
2
)= 0|
=
1
2
|8(-
+
) + k (-
-
) + 2(
+
)|= 0
|
-6k +
| = 0
|
- 6k|= 0
6k =
K =
6
K =
Clear