document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1177056>Question 1177056</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Place three vertices of a parallelogram ABCD at A(0, 0), B(2a, 2b)<BR>\n" );
document.write( "and D (2c, 2d).<BR>\n" );
document.write( "Use gradients to show that C = (2a + 2c, 2b + 2d) completes the<BR>\n" );
document.write( "parallelogram </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #839425 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=839425\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> slope of line = (y2-y1)/(x2-x1) where )x1,y1) and (x2,y2) are the two points on the line\r<BR>\n" );
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document.write( "Slope of AB = (2b-0)/(2a-0)= 2b/2a=b/a\r<BR>\n" );
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document.write( "slope of CD = b/a ( parallel to AB)\r<BR>\n" );
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document.write( "slope of line = (y2-y1)/(x2-x1) where )x1,y1) and (x2,y2) are the two points on the line\r<BR>\n" );
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document.write( "slope of CD = ((2b+2d)-2d) /( (2a+2c)-2c) = b/a \r<BR>\n" );
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document.write( "Therefore C = (2a + 2c, 2b + 2d) completes the<BR>\n" );
document.write( "parallelogram\r<BR>\n" );
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document.write( " </SPAN>\n" );
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