document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=12429>Question 12429</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question:\r<BR>\n" );
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document.write( "x²+y²=13<BR>\n" );
document.write( "2x+y=1\r<BR>\n" );
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document.write( "I then tried to solve by substitution:\r<BR>\n" );
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document.write( "y=1-2x<BR>\n" );
document.write( "x²+(1-2x)²=13\r<BR>\n" );
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document.write( "I then got a bit muddled up and wasn't sure how to expand (1-2x)²\r<BR>\n" );
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document.write( "But the answer i got would not factorise into two brackets so i decided to use the quadratic formula:\r<BR>\n" );
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document.write( "-b+/- sqrt ......<BR>\n" );
document.write( "but this did not get the correct answer of:\r<BR>\n" );
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document.write( "x=-1.2, y=3.4<BR>\n" );
document.write( "x=2, y=-3\r<BR>\n" );
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document.write( "Please help me because i don't have a clue what to do next! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #6327 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=6327\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What you did so far, looks right so far.  Let's expand the square of the binomial:\r<BR>\n" );
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document.write( "y=1-2x<BR>\n" );
document.write( "x²+(1-2x)²=13 \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+1+-+4x+%2B+4x%5E2+=+13 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+1+-+4x+%2B+4x%5E2+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5x%5E2+-+4x+-+12=+0 ALIGN=MIDDLE  ALT=\"5x%5E2+-+4x+-+12=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "By quadratic formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%284+%2B-+sqrt%2816-4%2A5%2A%28-12%29%29%29%2F%282%2A5%29 ALIGN=MIDDLE  ALT=\"x+=+%284+%2B-+sqrt%2816-4%2A5%2A%28-12%29%29%29%2F%282%2A5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%284+%2B-+sqrt%2816%2B240%29%29%2F10 ALIGN=MIDDLE  ALT=\"x+=+%284+%2B-+sqrt%2816%2B240%29%29%2F10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%284+%2B-+sqrt%28256%29%29%2F10 ALIGN=MIDDLE  ALT=\"x+=+%284+%2B-+sqrt%28256%29%29%2F10\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "This is the square root of a perfect square, which means that the original equation DOES factor, and the quadratic formula was not necessary in this case.  However, you are almost there now, so might as well finish it.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=+%284+%2B-+16%29%2F10 ALIGN=MIDDLE  ALT=\"x=+%284+%2B-+16%29%2F10\"   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=x=+%284%2B16%29%2F10+=+20%2F10+=+2 ALIGN=MIDDLE  ALT=\"x=+%284%2B16%29%2F10+=+20%2F10+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=+%284-16%29%2F10+=+%28-12%29%2F10+=+%28-6%29%2F5 ALIGN=MIDDLE  ALT=\"x=+%284-16%29%2F10+=+%28-12%29%2F10+=+%28-6%29%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Then solve for y using y = 1-2x<BR>\n" );
document.write( "If x= 2, y = 1-2*2= -3\r<BR>\n" );
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document.write( "If <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+-6%2F5 ALIGN=MIDDLE  ALT=\"x+=+-6%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+1+-+2%2A%28%28-6%29%2F5%29 ALIGN=MIDDLE  ALT=\"y+=+1+-+2%2A%28%28-6%29%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >= <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2B+12%2F5 ALIGN=MIDDLE  ALT=\"1%2B+12%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=17%2F5 ALIGN=MIDDLE  ALT=\"17%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Points of solution would be  (2,-3)  and (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++%28-6%29%2F5 ALIGN=MIDDLE  ALT=\"++%28-6%29%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=17%2F5 ALIGN=MIDDLE  ALT=\"17%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > ).\r<BR>\n" );
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document.write( "Check for errors in my work!!  Let me know if I made any.\r<BR>\n" );
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document.write( "R^2 at SCC </SPAN>\n" );
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