document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=147591>Question 147591</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Trapezoid ABCD has parallel sides AB and CD, a right angle at D, and the lengths AB = 15. BC = 10. and CD = 7. find the lenghth DA. \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #108418 by </B><A HREF=/tutors/aboutme.mpl?userid=orca><B>orca(409)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=orca><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=108418\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Draw CE perpendicular to AB.\r<BR>\n" );
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document.write( "In right triangle EBC, BC = 10, EB = 15 - 7 = 8, so EC = sqrt(10^2 - 8^2) = 6\r<BR>\n" );
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document.write( "As quadrilateral ADCE is a rectangle, so DA = CE.\r<BR>\n" );
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document.write( "Thus DA = EC = 6\r<BR>\n" );
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