document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=246121>Question 246121</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system:  y=2x+1   and x^2 + y^2 =25.  Do I do this with graphing or substitution?  Please provide solution\r<BR>\n" );
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document.write( "thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #179765 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=179765\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve the system: y=2x+1 and x^2 + y^2 =25. Do I do this with graphing or substitution? Please provide solution <BR>\n" );
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document.write( "Substitution:<BR>\n" );
document.write( "x^2 + (2x+1)^2 = 25<BR>\n" );
document.write( "x^2 + 4x^2 + 4x + 1 = 25<BR>\n" );
document.write( "5x^2 +4x - 24 = 0<BR>\n" );
document.write( "x = [-4+-sqrt(16 - 4*5*-24)]/10<BR>\n" );
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document.write( "x = [-4 +- sqrt(496)]/10<BR>\n" );
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document.write( "x = [-4 +- 4sqrt(31)]/10<BR>\n" );
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document.write( "x = [-2+2sqrt(31)]/5 or x = [-2-2sqrt(31)]/5<BR>\n" );
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document.write( "x = 1.8271 or x = -2.6271<BR>\n" );
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document.write( "Find the y-value associated with each of these x-values.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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