document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=16654>Question 16654</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It has been many years since I have had algebra. Please point me in the right direction with this system of linear equation...\r<BR>\n" );
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document.write( "x + 2y - 7z = -1<BR>\n" );
document.write( "3x + 7y - 24z = 6<BR>\n" );
document.write( "x + 4y - 12z = 26\r<BR>\n" );
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document.write( "Thank you from Montgomery, AL </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #8142 by </B><A HREF=/tutors/aboutme.mpl?userid=elima><B>elima(1433)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=elima><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=8142\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> eqn.1 x + 2y - 7z = -1<BR>\n" );
document.write( "eqn.2 3x + 7y - 24z = 6<BR>\n" );
document.write( "eqn.3 x + 4y - 12z = 26<BR>\n" );
document.write( "First of all you want to eliminate one of the variables, and to do that you need to add 2 equations together;<BR>\n" );
document.write( "We will take eqn.1 and eqn.3;but so we can eliminate a variable you will nee to multiply eqn.3 -1;<BR>\n" );
document.write( "(-1)x+4y-12z=26<BR>\n" );
document.write( "Now add them together;<BR>\n" );
document.write( "x+2y-7z=-1<BR>\n" );
document.write( "-x-4y+12z=-26<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "-2y+5z=-27 eqn.4<BR>\n" );
document.write( "Now we need to eliminate the x in another equation, so this time we will use eqn.1 and eqn.2, and multiply eqn.1 by -3;<BR>\n" );
document.write( "(-3)x+2y-7z=-1<BR>\n" );
document.write( "-3x-6y+21z=3<BR>\n" );
document.write( "Now we can add this and eqn. 2 together;<BR>\n" );
document.write( "-3x-6y+21z=3<BR>\n" );
document.write( "3x+7y-24z=6<BR>\n" );
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document.write( "y-3z=9 eqn.5<BR>\n" );
document.write( "Now we will use substitution to find one variable;<BR>\n" );
document.write( "We will find y in eqn.5;<BR>\n" );
document.write( "y=3z+9<BR>\n" );
document.write( "We will substitute the y in eqn.4;<BR>\n" );
document.write( "-2(3z+9)+5z=-27<BR>\n" );
document.write( "-6z-18+5z=-27<BR>\n" );
document.write( "Add 18 to each side and add like terms;<BR>\n" );
document.write( "-z=-27+18<BR>\n" );
document.write( "-z=-9<BR>\n" );
document.write( "z=9<BR>\n" );
document.write( "Now that we know what z= lets plug that into eqn.5;<BR>\n" );
document.write( "y-3(9)=9<BR>\n" );
document.write( "y-27=9<BR>\n" );
document.write( "y=36<BR>\n" );
document.write( "Now that we know what y and z = lets complete the problem by pluging them into eqn.1;<BR>\n" );
document.write( "x+2(36)-7(9)=-1<BR>\n" );
document.write( "x+72-63=-1<BR>\n" );
document.write( "x+9=-1<BR>\n" );
document.write( "x=-10<BR>\n" );
document.write( "Hope you inderstand, I know its hard to follow, it is a long problem.<BR>\n" );
document.write( "Good luck on your Algebra;<BR>\n" );
document.write( "=) </SPAN>\n" );
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