document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=254828>Question 254828</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a^2 – bc = 7, b^2 + ac = 7, c^2 + ab = 7, then determine the value of a^2 + b^2 + c^2. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #187123 by </B><A HREF=/tutors/aboutme.mpl?userid=vksarvepalli><B>vksarvepalli(154)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vksarvepalli><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=vksarvepalli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=187123\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  a^2 – bc = 7-------- 1<BR>\n" );
document.write( " b^2 + ac = 7-------- 2<BR>\n" );
document.write( " c^2 + ab = 7-------- 3\r<BR>\n" );
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document.write( "equating 1 and 2 <BR>\n" );
document.write( "  then 2 and 3 <BR>\n" );
document.write( "  then 3 and 1\r<BR>\n" );
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document.write( "we get either a=b+c<BR>\n" );
document.write( "        or    b=c=-a\r<BR>\n" );
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document.write( "but if b=c=-a the given equations will not satisfy\r<BR>\n" );
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document.write( "so a=b+c\r<BR>\n" );
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document.write( "now add the three equations 1,2 & 3\r<BR>\n" );
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document.write( "we get  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2%96bc%2Bc%5E2%2Bab%2Bb%5E2%2Bac=21 ALIGN=MIDDLE  ALT=\"a%5E2%96bc%2Bc%5E2%2Bab%2Bb%5E2%2Bac=21\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "=>   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2%2Bb%5E2%2Bc%5E2=21%2Bbc-a%28b%2Bc%29 ALIGN=MIDDLE  ALT=\"a%5E2%2Bb%5E2%2Bc%5E2=21%2Bbc-a%28b%2Bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "but since b+c=a\r<BR>\n" );
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document.write( "we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2%2Bb%5E2%2Bc%5E2=21%2Bbc-a%5E2 ALIGN=MIDDLE  ALT=\"a%5E2%2Bb%5E2%2Bc%5E2=21%2Bbc-a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "from eq. 1 bc-a^2=-7\r<BR>\n" );
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document.write( "substituting this in above eq \r<BR>\n" );
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document.write( "we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2%2Bb%5E2%2Bc%5E2=21-7 ALIGN=MIDDLE  ALT=\"a%5E2%2Bb%5E2%2Bc%5E2=21-7\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2%2Bb%5E2%2Bc%5E2=14 ALIGN=MIDDLE  ALT=\"a%5E2%2Bb%5E2%2Bc%5E2=14\"   DISABLED_style= \"max-width:90%; height:auto;\" >  Ans.\r<BR>\n" );
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document.write( "ans.  a^2+b^2+c^2=14 </SPAN>\n" );
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