Show that A(0, 0), B(5, 5) and C(-5, 5) are vertices of a right angled isosceles triangle.

Show that the points A(6, 4), B(9, 7) and C(11, 9) are collinear.

Calculate the distance between A(7, 3) and B on the x-axis whose abscissa is 11.

A is a point on the y-axis whose ordinate is 5 and B = (-3, 1). Find AB.