document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=272295>Question 272295</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solves these urgent problems!!!\r<BR>\n" );
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document.write( "first system\r<BR>\n" );
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document.write( "1. x^2+y^2=16<BR>\n" );
document.write( "     2x+y=4\r<BR>\n" );
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document.write( "second system\r<BR>\n" );
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document.write( "2. x^2+y^2=4<BR>\n" );
document.write( "     y=x^2-2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #199231 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=199231\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> first system <BR>\n" );
document.write( "1. x^2+y^2=16<BR>\n" );
document.write( "2x+y=4 --> y = -2x+4<BR>\n" );
document.write( "Sub for y into the 1st eqn<BR>\n" );
document.write( "x^2 + (-2x+4)^2 = 16<BR>\n" );
document.write( "x^2 + 4x^2 -16x + 16 = 16<BR>\n" );
document.write( "5x^2 - 16x = 0<BR>\n" );
document.write( "x = 0<BR>\n" );
document.write( "x = 16/5<BR>\n" );
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document.write( "Solve for y on the line, not the circle, to avoid extraneous roots<BR>\n" );
document.write( "x = 0, y = 4 --> (0,4)<BR>\n" );
document.write( "x = 16/5, y = -12/5 --> (3.2,-2.4)<BR>\n" );
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document.write( "second system <BR>\n" );
document.write( "2. x^2+y^2=4<BR>\n" );
document.write( "y=x^2-2 --> x^2 = y+2<BR>\n" );
document.write( "Sub for x^2<BR>\n" );
document.write( "(y+2) + y^2 = 4<BR>\n" );
document.write( "y^2 + y - 2 = 0<BR>\n" );
document.write( "(y+2)*(y-1) = o<BR>\n" );
document.write( "y = 1, y = -2<BR>\n" );
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document.write( "x^2 = y+2<BR>\n" );
document.write( "x^2 = 0 --> (0,-2)<BR>\n" );
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document.write( "x^2 = 3 --> (sqrt(3),1) and (-sqrt(3),1)<BR>\n" );
document.write( " </SPAN>\n" );
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