If the points `a+b,a-b and a+kb` be collinear, then k is equal to

If the points (a,b), (a',b') and (a-a',b-b') are collinear, then prove that ab' = a'b.

If the point (a,b), (a',b') and (a-a',b-b') are collinear, then prove that ab' = a'b.

If the points A(2,3),B(5,k) and C(6,7) are collinear then k is

If the points (a, b), (a', b') and (a-a', b-b') are collinear, show that ab' =a'b.

If the mid point between the points (a+b, a-b) and (-a, b) lies on the line ax+by=k , what is k equal to ?

If the points (-1,2-3),(4,a,1)and(b,8,5) are collinear, then a and b are respectively equal to

If the points A(3, -2), B(k, 2) and C(8, 8) are collinear then the value of k is