document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=376676>Question 376676</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve and check the following systems by elimination.  Show steps.  Check both equations.  <BR>\n" );
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document.write( "(3x – 4y = -30)<BR>\n" );
document.write( "(7x + 4y = 10 )\r<BR>\n" );
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document.write( "5.	<BR>\n" );
document.write( "(x – 4y = 29 )<BR>\n" );
document.write( "(3x + 2y = -11)\r<BR>\n" );
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document.write( "6.	<BR>\n" );
document.write( "(4x + 3y = -4)<BR>\n" );
document.write( "(3x – 7y = 34)<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #267946 by </B><A HREF=/tutors/aboutme.mpl?userid=sophxmai><B>sophxmai(62)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sophxmai><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=sophxmai><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=267946\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> #4	<BR>\n" );
document.write( "Equation 1:(3x – 4y = -30)<BR>\n" );
document.write( "Equation 2:(7x + 4y = 10) \r<BR>\n" );
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document.write( "Add the 2 equations, the y should cancel out.\r<BR>\n" );
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document.write( " 3x – 4y = -30<BR>\n" );
document.write( " 7x + 4y =  10<BR>\n" );
document.write( "10x + 0y = -20 <-- this simplifies to 10x = -20\r<BR>\n" );
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document.write( "From here, solve for x.<BR>\n" );
document.write( "10x = -20<BR>\n" );
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document.write( "x = -2\r<BR>\n" );
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document.write( "Now substitute x with x = -2 in one of the 2 equations.<BR>\n" );
document.write( "Equation 1:(3x – 4y = -30)\r<BR>\n" );
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document.write( "3x – 4y = -30<BR>\n" );
document.write( "3(-2) – 4y = -30<BR>\n" );
document.write( "-6 - 4y = -30<BR>\n" );
document.write( "-4y = -24<BR>\n" );
document.write( "y = 6\r<BR>\n" );
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document.write( "#5<BR>\n" );
document.write( "Equation 1:(x – 4y = 29)<BR>\n" );
document.write( "Equation 2:(3x + 2y = -11)\r<BR>\n" );
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document.write( "Multiply equation 1 by 3 so that the coefficient of x in both equations are the same.\r<BR>\n" );
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document.write( "x – 4y = 29<BR>\n" );
document.write( "3x - 12y = 87 <-- Let this be equation 3.\r<BR>\n" );
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document.write( "Now subtract equation 3 from equation 2.<BR>\n" );
document.write( "3x + 2y = -11<BR>\n" );
document.write( "3x - 12y = 87<BR>\n" );
document.write( "0x + 14y = -98 <-- This simplifies to 14y = -98\r<BR>\n" );
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document.write( "Solve for y.<BR>\n" );
document.write( "14y = -98<BR>\n" );
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document.write( "y = -7\r<BR>\n" );
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document.write( "Substitute y for y = -7 in one of the 3 equations.<BR>\n" );
document.write( "Equation 1:(x – 4y = 29)\r<BR>\n" );
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document.write( "x – 4y = 29<BR>\n" );
document.write( "x – 4(-7) = 29<BR>\n" );
document.write( "x + 28 = 29<BR>\n" );
document.write( "x = 1\r<BR>\n" );
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document.write( "Now try to do #6 by yourself using this method. If you need help with #6 after you've tried it, just message me.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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