Prove that the points (a, b), (c, d) and (a-c, b-d) are collinear, if ad = bc.

Prove that the (a, b+c), (b, c+a) and (c, a+b) are collinear.

If a, b, c be the pth, qth and rth terms respectively of a HP, show that the points (bc, p), (ca, q) and (ab, r) are collinear.

Show that points A(a,b+c),B(b,c+a) and C(c,a+b) are collinear

Show that the point P(a, b + c), Q(b, c +a) and R(c, a + b) are collinear.

Find the value of ‘b’ for which the points A(1, 2), B(-1, b) and C(-3, -4) are collinear .

The points A(-2,1) , B ( 0,5) , C ( -1 , 2) are collinear.

The points with coordinates (2a,3a), (3b,2b) and (c,c) are collinear

If the points A(-1, -4) , B(b,c) and C(5,-1) are collinear and 2b + c = 4 , find the values of b and c.

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

If the points A(x,y), B(a,0) and C(0,b) are collinear, prove that (x)/(a) + (y)/(b) = 1