a square.
http://wiki.answers.com/Q/What_shape_is_the_quadri...

The most standard type of quadrilateral is the square. It can be argued that
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It is called a square. "Regular" means all four angles are the same, and all four sides are the same. Source(s) http://en.wikipedia.org/wiki/Square_28g….
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An angle is formed when two lines (or line segments) meet at a single point. Angles are classified into distinct groups based on their measurement in degrees. Acute angles measure
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