document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1178014>Question 1178014</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A trapezium in which AD is parallel to BC and ∠ADC = ∠BCD = 90 °, The points A,B and C are (a,18), (12,-2) and (2,-7) respectively. Given that AB = 2BC, Find the value of a. Find the equation of AD. Find the equation of CD.Find the coordinates of D.Find the area of trapezium. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #807183 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=807183\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "D(BC )\r<BR>\n" );
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document.write( "Distance Equation Solution:<BR>\n" );
document.write( "d=sqrt((2−12)2+(−7−(−2)))\r<BR>\n" );
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document.write( "d=sqrt((−10)2+(−5)\r<BR>\n" );
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document.write( "d=sqrt((100+25))\r<BR>\n" );
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document.write( "d(BC)=√125\r<BR>\n" );
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document.write( "d(AB) \r<BR>\n" );
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document.write( "Distance Equation Solution:<BR>\n" );
document.write( "d=sqrt((a−12)^2+(18−(−2)^2))\r<BR>\n" );
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document.write( "d=sqrt((a^2-24a+144 +400))\r<BR>\n" );
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document.write( "d=sqrt( a^2-24a+544)\r<BR>\n" );
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document.write( "AB = 2BC\r<BR>\n" );
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document.write( "sqrt( a^2-24a+544) =10sqrt(5)\r<BR>\n" );
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document.write( "a^2-24a +544 =100*5\r<BR>\n" );
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document.write( "a^2-24a+44=0\r<BR>\n" );
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document.write( "a^2-22a-2a+44=0\r<BR>\n" );
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document.write( "(a-2)(a-22)=0\r<BR>\n" );
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document.write( "a=2 Or 22\r<BR>\n" );
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document.write( "slope of BC\r<BR>\n" );
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document.write( "Slope =y2−y1/x2−x<BR>\n" );
document.write( " of AD\r<BR>\n" );
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document.write( "−7−−2/2−12\r<BR>\n" );
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document.write( "−5/−10\r<BR>\n" );
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document.write( "1/2= slope of BC = slope of AD\r<BR>\n" );
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document.write( "equation of AD \r<BR>\n" );
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document.write( "use y = mx+c\r<BR>\n" );
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document.write( " </SPAN>\n" );
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