document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=310458>Question 310458</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given: Parallelogram ABCD is inscribed in a circle<BR>\n" );
document.write( "Prove: ABCD is a rectangle\r<BR>\n" );
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document.write( "I was thinking to start out saying that since parallelograms have congruent opposite sides, then the congruent chords would have congruent arcs, but then I got stuck. Could you please help me? I need this answer ASAP. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #221966 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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/cgi-bin/show-face.mpl?user=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=221966\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution:\r<BR>\n" );
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document.write( "LBAC= LBCD( opposite angles of a parallelogram are equal)<BR>\n" );
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document.write( "LBAC + LBCD = 180° ( opp. angles of a cyclic quadrilateral are  supplementary)<BR>\n" );
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document.write( "LBAC=LBCD= 90°<BR>\n" );
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document.write( "Similarly LABC=LADC=90°<BR>\n" );
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document.write( "ABCD is a rectangle ( all the angles are =90°)\r<BR>\n" );
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document.write( "L stands for angle </SPAN>\n" );
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