Recent content by za3raan

Sorry! I just saw that we can't use attachments to present question. I've edited the above post with the full question.

Homework Statement (a) Show that the four points r1 = (1, 0, 1), r2 = (4, 3, 5), r3 = (6, 4, 6) and r4 = (3, 1, 2) are coplanar and the vertices of a parallelogram. Let S be the closed planar region given by the interior and boundary of this parallelogram. An arbitrary point of S can be...