document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=122998>Question 122998</A>: <I><SPAN STYLE=\"word-break: break-all;\">  y = –3x\r<BR>\n" );
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document.write( "4x + y = 2\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #90346 by </B><A HREF=/tutors/aboutme.mpl?userid=johnnico6426><B>johnnico6426(16)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=johnnico6426><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=90346\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First of all, I assume since the question involves two linear equation that you are looking for the values of x and y.\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=linear_substitution.solver>SOLVE linear system by SUBSTITUTION</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT>Solve:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+system%28+%0D%0A++++3%5Cx+%2B+1%5Cy+=+0%2C%0D%0A++++4%5Cx+%2B+1%5Cy+=+2+%29%0D%0A++ ALIGN=MIDDLE  ALT=\"+system%28+%0D%0A++++3%5Cx+%2B+1%5Cy+=+0%2C%0D%0A++++4%5Cx+%2B+1%5Cy+=+2+%29%0D%0A++\"   DISABLED_style= \"max-width:90%; height:auto;\" >We'll use substitution. After moving 1*y to the right, we get:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2Ax+=+0+-+1%2Ay ALIGN=MIDDLE  ALT=\"3%2Ax+=+0+-+1%2Ay\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+0%2F3+-+1%2Ay%2F3 ALIGN=MIDDLE  ALT=\"x+=+0%2F3+-+1%2Ay%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Substitute that<BR>\n" );
document.write( "  into another equation:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2A%280%2F3+-+1%2Ay%2F3%29+%2B+1%5Cy+=+2 ALIGN=MIDDLE  ALT=\"4%2A%280%2F3+-+1%2Ay%2F3%29+%2B+1%5Cy+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and simplify: So, we know that y=-6. Since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+0%2F3+-+1%2Ay%2F3 ALIGN=MIDDLE  ALT=\"x+=+0%2F3+-+1%2Ay%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >, x=2.<BR>\n" );
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document.write( "  Answer: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28+x=2%2C+y=-6+%29 ALIGN=MIDDLE  ALT=\"system%28+x=2%2C+y=-6+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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document.write( "In other words, in you plug in -3x for y in the equation 4x + y = 2. The answer would come up as x=2. You then have to plug in 2 for x, which will yield y = 6.\r<BR>\n" );
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document.write( "The solution is (2,-6) </SPAN>\n" );
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