Vertices of a quadrilateral ABCD are A(1,1), B(5,6), C(10,10) and D(6,5). What is the shape of the quadrilateral?

A. Square
B. Rectangle but not a square
C. Rhombus
D. Parallelogram but not a rhombus
E. None of these

Your best bet on this one is to graph the points and see what you get.
It appears to be a rhombus -- which is a parallelogram with all sides equal --
You can calculate the lengths of the sides, or simply draw triangles as if you were going to use the Pythagorean Theorem to calculate lengths, and then confirm that all of the triangles are the same size.

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