2. Show that the points (7,9), (3,-7(, and (-3,3) are vertices of a right angled isosceles triangle.
3. Show that the points (4, -4), (-4,4), and (4√3, 4√3) are the vertices of an equilateral triangle.
4. Show that the set of points (-2,-1), (1,0), (4,3), and (1,2) are the vertices of a parallelogram.
5. Show that the set of points (2,-2), (8,4), (5,7), and (-1,1) are the vertices of a rectangle taken in order.
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