Question 182595
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Nothing.


In the first place, 'irragular' is not a word in the English language, so your question is meaningless on that basis.  But if, as I suspect, you meant <i><b>irregular</b></i>, the answer is the same.  By definition, a parallelogram must be regular.  It is impossible to have two sets of parallel sides on a quadrilateral and not have them be the same length.  Now, if what you <i><b>really</b></i> meant to ask is "What is an irregular <i><b>quadrilateral</b></i>, then the answer is as follows:


A quadrilateral is any plane figure with four straight sides.  An irregular quadrilateral is any quadrilateral that does not qualify as a parallelogram, trapezoid (trapezium if you are British), or kite.


I did not include square, rectangle, or rhombus in the excluded figures because they are all special cases of a parallelogram.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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