document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=572964>Question 572964</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am confused on how you go about solving this substitution problem \r<BR>\n" );
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document.write( "4y+3=3y+x<BR>\n" );
document.write( "2x+4y=18\r<BR>\n" );
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document.write( "I started to try doing this problem several different ways but I'm not sure how to solve it. Here's how I attempted to do it.<BR>\n" );
document.write( "4y+3=3y+x  I started by subtracting ( swinging )<BR>\n" );
document.write( "-4y -x -4y -x\r<BR>\n" );
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document.write( "= x-2=-1y<BR>\n" );
document.write( "     +2   +2<BR>\n" );
document.write( "-1/2x -1=y \r<BR>\n" );
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document.write( "2x+4=18<BR>\n" );
document.write( "2x+4( -1/2x-1)=18<BR>\n" );
document.write( "2x+ -2x -4=18<BR>\n" );
document.write( "0x-4=18<BR>\n" );
document.write( "    +4 +4<BR>\n" );
document.write( "0x=22<BR>\n" );
document.write( "Divide by 0 on each side.<BR>\n" );
document.write( "X=0<BR>\n" );
document.write( "-1/2(0)-1<BR>\n" );
document.write( "(0,1) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #368594 by </B><A HREF=/tutors/aboutme.mpl?userid=mathsmiles><B>mathsmiles(68)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathsmiles><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=mathsmiles><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=368594\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'm going to copy down what you have until I see a problem.\r<BR>\n" );
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document.write( "4y+3=3y+x  I started by subtracting ( swinging )<BR>\n" );
document.write( "-4y -x -4y -x\r<BR>\n" );
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document.write( "You tried doing 2 things at once to save a line of typing - literally - and messed yourself up.\r<BR>\n" );
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document.write( "Let me do what you're doing in 2 steps and you'll see:<BR>\n" );
document.write( "4y+3=3y+x<BR>\n" );
document.write( "-4y  -4y<BR>\n" );
document.write( "3 = -y+x<BR>\n" );
document.write( "Now subtract x from each side (although I'd have added y to each side so we get rid of those pesky minus signs):<BR>\n" );
document.write( "3  =-y+x<BR>\n" );
document.write( "-x    -x<BR>\n" );
document.write( "3-x = -y  (you had x-2=-1y)<BR>\n" );
document.write( "Now I have to multiply both sides by -1 to get y in it's more pleasant positive state :-)<BR>\n" );
document.write( "-1(3-x) = -1(-y)<BR>\n" );
document.write( "-3+x = y\r<BR>\n" );
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document.write( "Now go on with using this in the 2nd equation:<BR>\n" );
document.write( "2x+4y=18<BR>\n" );
document.write( "2x+4(-3+x)=18<BR>\n" );
document.write( "2x-12+4x=18<BR>\n" );
document.write( "2x-12= 18<BR>\n" );
document.write( "now add 12 to both sides:<BR>\n" );
document.write( "6x=30<BR>\n" );
document.write( "x=5\r<BR>\n" );
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document.write( "So y=-3+x = -3+5 = 2\r<BR>\n" );
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document.write( "Checking:<BR>\n" );
document.write( "4(2)+3 = 3(2)+5<BR>\n" );
document.write( "8+3 = 6+5<BR>\n" );
document.write( "11=11 Correct<BR>\n" );
document.write( "2(5)+4(2)= 18<BR>\n" );
document.write( "10+8=18<BR>\n" );
document.write( "18=18 Correct!\r<BR>\n" );
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document.write( "Please, don't conserve so much!  Really, think of how much that one line of savings really cost you in time and aggravation tonight.  Write out each step.  You'll have a much better chance, especially on a test, to not miss a step.  The pros do it, so should you.  :-)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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