document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1190677>Question 1190677</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2x+y=-4<BR>\n" );
document.write( "x+y=-7<BR>\n" );
document.write( "Find the first variable and isolate it. Then solve for that variable.<BR>\n" );
document.write( "solve for the second variable <BR>\n" );
document.write( "find the numerical value of the first variable.<BR>\n" );
document.write( "(when I say the first variable it's any variable that you would want to start with...that's what my teacher said)<BR>\n" );
document.write( "I don't really understand how to do this so could somebody please explain  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #822373 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=822373\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> your equations are:\r<BR>\n" );
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document.write( "2x + y = -4<BR>\n" );
document.write( "x + y = -7\r<BR>\n" );
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document.write( "solve for x in the second equation to get:\r<BR>\n" );
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document.write( "x = -7 - y\r<BR>\n" );
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document.write( "replace x in the first equation with that to get:\r<BR>\n" );
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document.write( "2x + y = -4 becomes  2 * (-7 - y) + y = -4.\r<BR>\n" );
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document.write( "you have just changed one equation with two variable into one equation with one variable, allowing you to solve for that variable.\r<BR>\n" );
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document.write( "the equation to solve is:\r<BR>\n" );
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document.write( "2 * (-7 - y) + y = -4.<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "-14 - 2y + y = -4<BR>\n" );
document.write( "combine like terms to get:<BR>\n" );
document.write( "-14 - y = -4<BR>\n" );
document.write( "add 14 to both sides to get:<BR>\n" );
document.write( "-y = -4 + 14<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "-y = 10<BR>\n" );
document.write( "multiply both sides by -1 to get:<BR>\n" );
document.write( "y = -10\r<BR>\n" );
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document.write( "now that you solved for y, you can go back to your original equations to solve for x.\r<BR>\n" );
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document.write( "your original equations are:<BR>\n" );
document.write( "2x + y = -4<BR>\n" );
document.write( "x + y = -7\r<BR>\n" );
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document.write( "when y = -10 .....<BR>\n" );
document.write( "2x + y = -4 becomes 2x -10 = -4 which becomes 2x = 6 which becomes x = 3.<BR>\n" );
document.write( "x + y = -7 becomes x - 10 = -7  which becomes x = 3.<BR>\n" );
document.write( "your solution is that y = -10 and x = 3.<BR>\n" );
document.write( "both original equations are true with those values for x and y.\r<BR>\n" );
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document.write( "let me know if you have any questions or need further clarification.\r<BR>\n" );
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document.write( "here's a reference for you as well.<BR>\n" );
document.write( "<a  rel=nofollow HREF= \"https://www.purplemath.com/modules/systlin4.htm\" target = \"_blank\">https://www.purplemath.com/modules/systlin4.htm</a><BR>\n" );
document.write( "theo </SPAN>\n" );
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