A concave quadrilateral. An arrowhead or a delta, for example.
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A convex quadrilateral is a 4sided figure in which each vertex lies in the interior
http://www.chacha.com/question/whatisaconvexqu...

A quadrilateral is convex if each vertex lies in the interior of the opposite angle. Ask away!
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F. The sum of the interior angles a quadrilateral is always 360 degrees. Think about a rectangle. All of the angles are 90, so the sum is 360. If one of your angles are 102, and the
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