document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=125832>Question 125832</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618250182/algebrahomeworkh>Algebra I</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> This is my son'd hoework assignment, in the back of the book on page 803 in the extra practice section he has to solve proble # 18using linear combinations to solve linear equations. The problem is:\r<BR>\n" );
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document.write( "3x+7y=-1<BR>\n" );
document.write( "7y=-6x\r<BR>\n" );
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document.write( "If I rearrange the equation to solve it looks like this:\r<BR>\n" );
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document.write( " 3x+7y=-1<BR>\n" );
document.write( "-6x-7y=?\r<BR>\n" );
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document.write( "Now what do we do? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #92216 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=92216\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve using linear combinations:<BR>\n" );
document.write( "1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%2B7y+=+-1 ALIGN=MIDDLE  ALT=\"3x%2B7y+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y+=+-6x ALIGN=MIDDLE  ALT=\"7y+=+-6x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You had the right idea in rearranging the second equation but the ? should be a 0, as in:<BR>\n" );
document.write( "2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-6x-7y+=+0 ALIGN=MIDDLE  ALT=\"-6x-7y+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now you add the two equations:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%2B7y+=+-1 ALIGN=MIDDLE  ALT=\"3x%2B7y+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-6x-7y+=+0 ALIGN=MIDDLE  ALT=\"-6x-7y+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x+=+-1 ALIGN=MIDDLE  ALT=\"-3x+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now divide both sides by -3.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+1%2F3 ALIGN=MIDDLE  ALT=\"x+=+1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now substitute this value of x into either one of the two original equations to solve for y. Let's use the second equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y+=+-6x ALIGN=MIDDLE  ALT=\"7y+=+-6x\"   DISABLED_style= \"max-width:90%; height:auto;\" > Substitute <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+1%2F3 ALIGN=MIDDLE  ALT=\"x+=+1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y+=+-6%281%2F3%29 ALIGN=MIDDLE  ALT=\"7y+=+-6%281%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y+=+-2 ALIGN=MIDDLE  ALT=\"7y+=+-2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now divide both sides by 7.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-2%2F7 ALIGN=MIDDLE  ALT=\"y+=+-2%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );