A concave quadrilateral. An arrowhead or a delta, for example.
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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
http://answers.yahoo.com/question/index?qid=201205...

A quadrilateral is a shape that always has four sides (Quadmeans 4) Some examples of quadrilateral are: squares, rhombus, parallelogram,kite. Even though these shapes are quadrilaterals
http://www.ask.com/webanswers/Science/Mathematics...

A convex quadrilateral interior angle atsup to 4 degrees. Thanks fo...
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