document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=795381>Question 795381</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this application of systems of linear equations problem:\r<BR>\n" );
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document.write( "Each course at a community college is worth 1 or 2 credits. A group of students is taking a total of 26 courses that are worth a total of 39 credits. How many 1- credit courses are being taken? How many 2- credit courses are being taken?\r<BR>\n" );
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document.write( "I know that I need a system of linear equations. I made x equal the number of 1 credit courses and y equal the number of 2 credits courses. The first linear equation I made from the information provided is  x + y= 39, but that's as far as I got.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #481186 by </B><A HREF=/tutors/aboutme.mpl?userid=cahlove><B>cahlove(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=cahlove><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=481186\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Your first equation should be:<BR>\n" );
document.write( "x + y = 26<BR>\n" );
document.write( "The 2nd equation should be:<BR>\n" );
document.write( "1x + 2y = 39\r<BR>\n" );
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document.write( "Now that we know the two equations we can use the addition/ elimination method to find our answer.<BR>\n" );
document.write( "Let's use the first equation, since the coefficients are 1. <BR>\n" );
document.write( "We will multiply the first equation by -2 so the Y variable will cancel out.<BR>\n" );
document.write( "-2(x + y = 26)<BR>\n" );
document.write( "-2x - 2y = -52\r<BR>\n" );
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document.write( "Now that the Y variables are the same, we can add equation two and the new equation we made.<BR>\n" );
document.write( " -2x - 2y = -52 <BR>\n" );
document.write( "+ 1x + 2y =  39<BR>\n" );
document.write( "  -1x     =  -13<BR>\n" );
document.write( "    x  =  13\r<BR>\n" );
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document.write( "Now that we have x we can plug in back into the original equations to find the value of the y variable. We will use the first equation since it is easier. <BR>\n" );
document.write( "x + y = 26<BR>\n" );
document.write( "13 + y = 26<BR>\n" );
document.write( "     y = 13\r<BR>\n" );
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document.write( "To check your work, plug x = 13 and y = 13 back into equations 1 and 2.<BR>\n" );
document.write( "Equation 1<BR>\n" );
document.write( "x + y = 26<BR>\n" );
document.write( "13 + 13 = 26<BR>\n" );
document.write( "26 = 26<BR>\n" );
document.write( "Equation 2<BR>\n" );
document.write( "1x +2y = 39<BR>\n" );
document.write( "1(13) + 2(13) = 39<BR>\n" );
document.write( "13 + 26 = 39<BR>\n" );
document.write( "39 = 39\r<BR>\n" );
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document.write( "How many 1- credit courses are being taken? Thirteen 1- credit courses were taken<BR>\n" );
document.write( "How many 2- credit courses are being taken? Thirteen 2- credit courses were taken </SPAN>\n" );
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