document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=137499>Question 137499</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve by the substitution method.\r<BR>\n" );
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document.write( "4x+7y = 34\r<BR>\n" );
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document.write( "-3x+y =  12\r<BR>\n" );
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document.write( "Can someone please HELP me with this problem. I do not understand it at all!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100616 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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=100616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Given: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B7y+=+34 ALIGN=MIDDLE  ALT=\"4x%2B7y+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x%2By+=++12 ALIGN=MIDDLE  ALT=\"-3x%2By+=++12\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solve using substitution. You have 2 equations and two unknowns, so you can solve this.\r<BR>\n" );
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document.write( "When using substitution to solve equations like these, you use the following steps:\r<BR>\n" );
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document.write( "1) Use the first equation to find one of the variables in terms of the other variable. We will use <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B7y+=+34 ALIGN=MIDDLE  ALT=\"4x%2B7y+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" > and find y in terms of x.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B7y+=+34 ALIGN=MIDDLE  ALT=\"4x%2B7y+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y+=+%2834+-+4x%29 ALIGN=MIDDLE  ALT=\"7y+=+%2834+-+4x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+%2834+-+4x%29%2F7 ALIGN=MIDDLE  ALT=\"y+=+%2834+-+4x%29%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "2) Use the value found in step 1 for y as input to the second equation. Once you substitute the value for y from step 1 into equation 2, you have an a single equation with a single variable.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x%2By+=++12 ALIGN=MIDDLE  ALT=\"-3x%2By+=++12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x+%2B+%28%2834+-+4x%29%2F7%29+=+12 ALIGN=MIDDLE  ALT=\"-3x+%2B+%28%2834+-+4x%29%2F7%29+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "3) Now solve for the variable x<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-21x+%2B+34+-4x+=+84 ALIGN=MIDDLE  ALT=\"-21x+%2B+34+-4x+=+84\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-25x+=+50 ALIGN=MIDDLE  ALT=\"-25x+=+50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2+=+x ALIGN=MIDDLE  ALT=\"-2+=+x\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "4) Using the value from step 3 for x, substitute back into any of the original equation or the equation from step 1, to solve for y. Just pick one equation that seems easiest to use.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x%2By+=++12 ALIGN=MIDDLE  ALT=\"-3x%2By+=++12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3%2A%28-2%29+%2B+y+=+12 ALIGN=MIDDLE  ALT=\"-3%2A%28-2%29+%2B+y+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6+%2B+y+=+12 ALIGN=MIDDLE  ALT=\"6+%2B+y+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+6 ALIGN=MIDDLE  ALT=\"y+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "5) Check your answer. Use the two values you've found for x and y in the 'other' original equation to verify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B7y+=+34 ALIGN=MIDDLE  ALT=\"4x%2B7y+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2A%28-2%29+%2B+7%2A%286%29+=+34 ALIGN=MIDDLE  ALT=\"4%2A%28-2%29+%2B+7%2A%286%29+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-8+%2B+42+=+34 ALIGN=MIDDLE  ALT=\"-8+%2B+42+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=34+=+34 ALIGN=MIDDLE  ALT=\"34+=+34\"   DISABLED_style= \"max-width:90%; height:auto;\" > which is true.\r<BR>\n" );
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document.write( "So the answer is (-2,6)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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