document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=69915>Question 69915</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am confused on how to solve systems using equations.<BR>\n" );
document.write( "here is the problem: \r<BR>\n" );
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document.write( "x-2y=-8<BR>\n" );
document.write( "y= -x - 2\r<BR>\n" );
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document.write( "so far i have tried this:<BR>\n" );
document.write( "x+-2y=-8<BR>\n" );
document.write( "  -2  -2\r<BR>\n" );
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document.write( "x=8-2y<BR>\n" );
document.write( "2y=-8 +2<BR>\n" );
document.write( "i am confused on what i am doing wrong.<BR>\n" );
document.write( "can you help?\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 #49831 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=49831\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Substitution seems to be the most straightforward way of solving this system:\r<BR>\n" );
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document.write( "(1)    x-2y=-8<BR>\n" );
document.write( "(2)    y= -x - 2 \r<BR>\n" );
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document.write( "Look at eq (2)<BR>\n" );
document.write( "y=-x-2<BR>\n" );
document.write( "-y=x+2<BR>\n" );
document.write( "-2y=2x+4-----------substitute this into (1) and we get:\r<BR>\n" );
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document.write( "x+2x+4=-8  subtract 4 from both sides<BR>\n" );
document.write( "3x=-8-4<BR>\n" );
document.write( "3x=-12  divide both sides by 3<BR>\n" );
document.write( "x=-4\r<BR>\n" );
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document.write( "substitute x=-4 into (2) and we get:\r<BR>\n" );
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document.write( "y=4-2<BR>\n" );
document.write( "y=2\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "(1)  x-2y=-8<BR>\n" );
document.write( "-4-2(2)=-8<BR>\n" );
document.write( "-8=-8\r<BR>\n" );
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document.write( "(2)   y=-x-2<BR>\n" );
document.write( "2=4-2<BR>\n" );
document.write( "2=2\r<BR>\n" );
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document.write( "Another approach, similar to what you were doing, is as follows:\r<BR>\n" );
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document.write( "(1)    x-2y=-8<BR>\n" );
document.write( "(2)    y=-x -2 re-arrange by subtracting y and adding 2 to both sides:\r<BR>\n" );
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document.write( "(1)    x-2y=-8<BR>\n" );
document.write( "(2)    y-y+2=-x-y-2+2  collecting like terms: \r<BR>\n" );
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document.write( "(1)    x-2y=-8<BR>\n" );
document.write( "(2)    2=-x-y or -x-y=2\r<BR>\n" );
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document.write( "(1)    x-2y=-8<BR>\n" );
document.write( "(2)   -x-y=2\r<BR>\n" );
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document.write( "Add (1) and (2)<BR>\n" );
document.write( "-3y=-6  divide both sides by -3<BR>\n" );
document.write( "y=2\r<BR>\n" );
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document.write( "substitute y=2 in (1)<BR>\n" );
document.write( "x-2*2=-8<BR>\n" );
document.write( "x-4=-8  add 4 to both sides<BR>\n" );
document.write( "x=-4\r<BR>\n" );
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document.write( "Hope this helps-----ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
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