document.write( "Question 1110545: Prove that if both pairs of opposite sides of a quadrilateral are congruent, then the quadrilateral is a parallelogram. \n" ); document.write( "
Algebra.Com's Answer #725542 by ikleyn(52787)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "See the lesson\r
\n" ); document.write( "\n" ); document.write( "    - Properties of the sides of a parallelogram, Theorem 2\r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook on Geometry\r
\n" ); document.write( "\n" ); document.write( "    GEOMETRY - YOUR ONLINE TEXTBOOK \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the topic \"Properties of parallelograms\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in GEOMETRY
\n" ); document.write( "https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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