document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=216318>Question 216318</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the system of linear equations {4x+y=7<BR>\n" );
document.write( "                                       {x-2y=13<BR>\n" );
document.write( "i am at a loss... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #163356 by </B><A HREF=/tutors/aboutme.mpl?userid=ichudov><B>ichudov(507)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ichudov><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=ichudov><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=163356\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <TABLE  BORDER=1>\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++++4%5Cx+%2B+1%5Cy+=+7%2C%0D%0A++++1%5Cx+%2B+-2%5Cy+=+13+%29%0D%0A++ ALIGN=MIDDLE  ALT=\"+system%28+%0D%0A++++4%5Cx+%2B+1%5Cy+=+7%2C%0D%0A++++1%5Cx+%2B+-2%5Cy+=+13+%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=4%2Ax+=+7+-+1%2Ay ALIGN=MIDDLE  ALT=\"4%2Ax+=+7+-+1%2Ay\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+7%2F4+-+1%2Ay%2F4 ALIGN=MIDDLE  ALT=\"x+=+7%2F4+-+1%2Ay%2F4\"   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=1%2A%287%2F4+-+1%2Ay%2F4%29+%2B+-2%5Cy+=+13 ALIGN=MIDDLE  ALT=\"1%2A%287%2F4+-+1%2Ay%2F4%29+%2B+-2%5Cy+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" > and simplify: So, we know that y=-5. Since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+7%2F4+-+1%2Ay%2F4 ALIGN=MIDDLE  ALT=\"x+=+7%2F4+-+1%2Ay%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >, x=3.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Answer: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28+x=3%2C+y=-5+%29 ALIGN=MIDDLE  ALT=\"system%28+x=3%2C+y=-5+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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