document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=638214>Question 638214</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solving System of Linear Equations by Elimination. My math this week shows an example and I do not understand where the answer comes from. I will provide the example and show where I got lost. <BR>\n" );
document.write( " 2a + 3b = 25<BR>\n" );
document.write( "-2a + b = 11\r<BR>\n" );
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document.write( "I understand this section <BR>\n" );
document.write( " 2a + 3b = 25<BR>\n" );
document.write( "-2a +  b = 11<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "      4b = 36<BR>\n" );
document.write( "     ___  ___<BR>\n" );
document.write( "      4    4    = b=9\r<BR>\n" );
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document.write( "2a + 3(9)= 25 <----- this is where my confusion is: the answer it shows it as -1 BUT HOW DID IT GET THIS ANSWER?\r<BR>\n" );
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document.write( "I get the fact that it is a point, I see that the answer is (-1,9) but I do not know how to get the -1, I do know where the 9 came from but not the -1. <BR>\n" );
document.write( "I hope this is example enough for help. I have similar questions that I have due but I cannot find out the correct answer if I am missing this one step. \r<BR>\n" );
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document.write( "I did one with out the example and came to the same problem of finding one point  but not the other. I got it wrong because of that one missing part. I will also show what I did.\r<BR>\n" );
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document.write( "6a + 5b = 17<BR>\n" );
document.write( "-6a + b = 25\r<BR>\n" );
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document.write( "6a + 5b = 17<BR>\n" );
document.write( "-6a + b = 25<BR>\n" );
document.write( "_____________<BR>\n" );
document.write( "      6b = 42<BR>\n" );
document.write( "      ___  ___<BR>\n" );
document.write( "       6    6    which is b = 7\r<BR>\n" );
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document.write( "6a + 5(7)=17.....AGAIN I AM STUCK! the correct answer was -3 but I do not see how? \r<BR>\n" );
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document.write( "Also is there a easier way of doing this math? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #537811 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=537811\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> second system<BR>\n" );
document.write( "b = 7 <BR>\n" );
document.write( "now get a which is -3\r<BR>\n" );
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document.write( "6,5,17<BR>\n" );
document.write( "-6,1,25\r<BR>\n" );
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document.write( "divide row 1 by 6/1<BR>\n" );
document.write( "1,5/6,17/6<BR>\n" );
document.write( "-6,1,25\r<BR>\n" );
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document.write( "add  down (6/1) *row 1 to row 2<BR>\n" );
document.write( "1,5/6,17/6<BR>\n" );
document.write( "0,6,42\r<BR>\n" );
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document.write( "divide row 2 by 6/1<BR>\n" );
document.write( "1,5/6,17/6<BR>\n" );
document.write( "0,1,7\r<BR>\n" );
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document.write( "We now have the value for the last variable.<BR>\n" );
document.write( "We will work our way up and get the other solutions.\r<BR>\n" );
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document.write( "add up  (-5/6) *row 2 to row 1<BR>\n" );
document.write( "1,0,-3<BR>\n" );
document.write( "0,1,7\r<BR>\n" );
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document.write( "final<BR>\n" );
document.write( "1,0,-3<BR>\n" );
document.write( "0,1,7\r<BR>\n" );
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document.write( "1,0,-3<BR>\n" );
document.write( "0,1,7\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );