document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=80571>Question 80571</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the equation and check for extraneous solutions.<BR>\n" );
document.write( "square root 9a^2 +a-7 = 3a </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #58521 by </B><A HREF=/tutors/aboutme.mpl?userid=mathdoc314><B>mathdoc314(58)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathdoc314><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=58521\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I guess that means you want values of a for which \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+sqrt%289%2Aa%5E2+%2B+a+-+7%29+=+3a+ ALIGN=MIDDLE  ALT=\"+sqrt%289%2Aa%5E2+%2B+a+-+7%29+=+3a+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The extraneous solutions that can occur are ones with <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+%3C+0+ ALIGN=MIDDLE  ALT=\"+a+%3C+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "since the left side is always nonnegative.  (The question doesn't ask for solutions where + or - square root of 9a^2 + a - 7 is 3a.)\r<BR>\n" );
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document.write( "Square both sides\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+9%2Aa%5E2+%2B+a+-+7+=+9%2Aa%5E2+ ALIGN=MIDDLE  ALT=\"+9%2Aa%5E2+%2B+a+-+7+=+9%2Aa%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%3E=0+ ALIGN=MIDDLE  ALT=\"+a%3E=0+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Subtract 9*a^2 from both sides\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a-7+=+0+ ALIGN=MIDDLE  ALT=\"+a-7+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%3E=+0+ ALIGN=MIDDLE  ALT=\"+a%3E=+0+\"   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=+a+=+7+ ALIGN=MIDDLE  ALT=\"+a+=+7+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Check your answer:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+sqrt%289%2A7%5E2+%2B+7+-+7%29+=+3%2A7+ ALIGN=MIDDLE  ALT=\"+sqrt%289%2A7%5E2+%2B+7+-+7%29+=+3%2A7+\"   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=+sqrt%28441%29+=+21+ ALIGN=MIDDLE  ALT=\"+sqrt%28441%29+=+21+\"   DISABLED_style= \"max-width:90%; height:auto;\" > TRUE\r<BR>\n" );
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document.write( " </SPAN>\n" );
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