Show that the points (taken in order)
(8,4),(5,7),(-1,1),(2,-2) form a rectangle.

Show that the points (taken in order) (-3,1),(-6,-7),(3,-9),(6,-1) form a parallelogram.

Show that the points (taken in order) (3,-2),(7,6),(-1,2),(-5,-6) form a rhombus.

Show that the following points are collinear. (-1,7) ,(3,-5), (4,-8)

Show that the points (-2,5),(3,-4),(7,10) form a right angled isosceles triangle.

Show that the points (1, 2, -2), (2, 3, -4) and (3, 4, -3) form a right angled triangle.

Show that the points (4,-2), (2,-4), (7,1) are collinear.

Show that the points ( 1,0),(2,-7) , (8,1) and (9,-6) are concyclic.

If the area of the quadrilateral whose angular points taken in order are (1, 2), (-5, 6), (7, -4) and (h, -2) be zero, show that h=3 .

Show that the points A(2,3,5),B(-4,7,-7),C(-2,1,-10) and D(4,-3,2) are the vertices of a rectangle.

Show that the points (4,7,8),(2,3,4),(-1,-2,1) ,(1,2,5) are the vertices of a paralelogram.