document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=320857>Question 320857</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given DE = FG EG = GH Prove DG = FH and GIVE REASONS!\r<BR>\n" );
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document.write( "Given QR = ST Prove QS = RT </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #229822 by </B><A HREF=/tutors/aboutme.mpl?userid=toidayma><B>toidayma(44)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=toidayma><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=toidayma><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=229822\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ___D___E____F___G________H____<BR>\n" );
document.write( "We have:<BR>\n" );
document.write( "DG = DE + EG<BR>\n" );
document.write( "   = DE + GH (since EG = GH)<BR>\n" );
document.write( "   = FG + GH (since DE = FG)<BR>\n" );
document.write( "   = FH<BR>\n" );
document.write( "Is that what you need?<BR>\n" );
document.write( "Actually, there are many possible positions of given points on a line (the example I draw above is just one of them). But you can use the same solution to prove it. (this solution is always correct if all the information you give is vector, not line)<BR>\n" );
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document.write( "The second part of your question is not clear enough. If they are vectors, it is easy.<BR>\n" );
document.write( "vQR = vST (v = vector)<BR>\n" );
document.write( "we have:<BR>\n" );
document.write( "vQS = vQR + vRS<BR>\n" );
document.write( "    = vST + vRS (since vQR = vST)<BR>\n" );
document.write( "    = vRT<BR>\n" );
document.write( "That's what to prove. Right? </SPAN>\n" );
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