document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=169616>Question 169616</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how can i proof that diagonals bisect each other in a parallelogram </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #125073 by </B><A HREF=/tutors/aboutme.mpl?userid=gonzo><B>gonzo(654)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=gonzo><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=125073\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let ABCD be your parallelogram<BR>\n" );
document.write( "A is bottom left<BR>\n" );
document.write( "B is top left<BR>\n" );
document.write( "C is top right<BR>\n" );
document.write( "D is bottom right.<BR>\n" );
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document.write( "let ABCD lean to the right so that point B is slightly to the right of point A.<BR>\n" );
document.write( "all you need is a little tilt to show that it's not a rectangle.<BR>\n" );
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document.write( "draw diagonals AC and BD.<BR>\n" );
document.write( "AC is the long diagonal and BD is the short diagonal.<BR>\n" );
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document.write( "BC congruent to AD (opposite sides of a parallelogram are congruent)<BR>\n" );
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document.write( "note:<BR>\n" );
document.write( "AC and BD are diagonals of the parallelogram.<BR>\n" );
document.write( "they are also transversals that intersect two parallel lines (BC and AD).<BR>\n" );
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document.write( "angle ACB congruent to angle CAD (opposite internal angles caused by the intersection of a transversal with two parallel lines are congruent).<BR>\n" );
document.write( "likewise, angle DBC congruent to angle BDA.<BR>\n" );
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document.write( "you have triangles AED congruent to triangle CEB (ASA)<BR>\n" );
document.write( "the ASA is formed by:<BR>\n" );
document.write( "side BC congruent to side AD<BR>\n" );
document.write( "angle ACB congruent to angle CAD<BR>\n" );
document.write( "angle DBC congruent to angle BDA.<BR>\n" );
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document.write( "CE is congruent to AE (corresponding parts of congruent triangles are congruent)<BR>\n" );
document.write( "BE is congruent to DE (same reason).<BR>\n" );
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document.write( "a sketch of the parallelogram can be found at this website:<BR>\n" );
document.write( "www.geocities.com/gonzo89p<BR>\n" );
document.write( "look for 169616 parallelogram<BR>\n" );
document.write( "shouldn't be too hard to find.<BR>\n" );
document.write( "it's the only one there.<BR>\n" );
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