Find `a`, for which the points `A(3, 2, 1), B(4, a, 5), C(4, 2, -2)` and `D(6, 5, -1)` are coplanar.

Find lambda for which the points A(3,2,1),B(4,lambda,5),C(4,2,-2) and D(6,5,-1) are coplanar.

Find the value of 'x' for which the four points : A(x, -1, -1), B(4, 5, 1), C(3, 9, 4) and D(-4, 4, 4) are coplanar.

The value of k for which the points A (1, 0, 3), B(-1, 3, 4), C(1, 2, 1) and D(k, 2, 5) are coplanar, are

Find the value of x, if the points A(3,2,1),B(4,x,5),C(4,2,2)and(6,5,-1) are coplanar.

Show that the points A(2, -1, 0) B(-3, 0, 4), C(-1, -1, 4) and D(0, -5, 2) are non coplanar.

If the points A(2, -1, 1), B(4, 0, p), C(1, 1, 1), D(2, 4, 3) are coplanar, then p=

Prove that the points A(0, 4, 1), B(2, 3, -1), C(4, 5, 0) and D(2, 6, 2) are vertices of a square.

If the points A(3, 9, 4), B(0, -1, -1), C(lambda, 4, 4), D(4, 5, 1) are coplanar, then lambda=

Show that the points A(-1,4,-3),B(3,2,-5),C(-3,8,-5) and D(-3,2,1) are coplanar.

If the points A(4, 5, 1), B(5, 3, 4), C(4, 1, 6), D(3, lambda, 3) are coplanar, then lambda=