Show that the points `A(,1,2,3),B(-1,-2,-1),C(2,3,2) and D(4,7,6)` are the vertices of a parallelogram ABCD but it is not a rectangle.

Show that the points A(1,2,3),B(-1,-2,-1),C(2,3,2) and D(4,7,6) are the vertices of a parallelogram ABCD but not a rectangle.

Show that the points A(1,2,3),B(-1,-2,-1)C(2,3,2),D(4,7,6) are the vertices of a parallelogram.

Show that the points (1, 2, 3), (-1, -2, -1), (2, 3, 2) and (4, 7, 6) are the vertices of a parallelogram.

Show that the points (3,-1,-1),(5,-4,0) ,(2,3,-2) and (0,6,-3) are the vertices of a parallelogram

Show that the points A(3, 1), B(0, -2), C(1, 1) and D(4, 4) are the vertices of a parallelogram ABCD.

Show that the point (3,-1,-1), (5,-4,0), (2,3,-2) and (0,6,-3) are the vertices of a parallelogram.

Show that the points (3,-1,-1),(5,-4,0),(2,3,-2) and (0,6,-3) are the vertices of a parallelogram

Show that the points A(3,3,3,),B(0,6,3),C(1,7,7) and D(4,4,7) are the vertices of a square.

Show that the point A(1, 3, 0), B(–5, 5,, 2), C(–9, –1, 2) and D(–3, –3, 0) are the vertices of a parallelogram ABCD, but it is not a rectangle.

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