document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=748072>Question 748072</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The distance between the two points A(a,1,2)  and B(5,a,3) is 3. Find the value of . </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #455317 by </B><A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><B>tommyt3rd(5050)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><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=tommyt3rd><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=455317\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If you mean find the value of a, then here we go:\r<BR>\n" );
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document.write( "It's convenient to use distance squared in this case (why?)<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A3%5E2=%285-a%29%5E2%2B%28a-1%29%5E2%2B%283-2%29%5E2%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0A3%5E2=%285-a%29%5E2%2B%28a-1%29%5E2%2B%283-2%29%5E2%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A9=%2825-10a%2Ba%5E2%29%2B%28a%5E2-2a%2B1%29%2B%0D%0A1 ALIGN=MIDDLE  ALT=\"%0D%0A9=%2825-10a%2Ba%5E2%29%2B%28a%5E2-2a%2B1%29%2B%0D%0A1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "and after some simplifying and rearranging\r<BR>\n" );
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document.write( "then<BR>\n" );
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document.write( "which is a perfect square and tells us a=3\r<BR>\n" );
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