document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=35917>Question 35917</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0134333381/algebrahomeworkh>Prentice Hall Algebra Tools For A Changing World</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> 3x-y=21<BR>\n" );
document.write( "2x+y=4\r<BR>\n" );
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document.write( "Describe a first step for solving each system using elimination. then solve each system. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #22016 by </B><A HREF=/tutors/aboutme.mpl?userid=tran3209><B>tran3209(100)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tran3209><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=22016\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The two equations:\r<BR>\n" );
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document.write( "3x-y=21\r<BR>\n" );
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document.write( "2x+y=4\r<BR>\n" );
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document.write( "Step 1.\r<BR>\n" );
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document.write( "Solve for one of the varriables first.Simplfy the equation. \r<BR>\n" );
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document.write( "2x+y=4\r<BR>\n" );
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document.write( "subtract 2x from both sides\r<BR>\n" );
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document.write( "y=-2x+4\r<BR>\n" );
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document.write( "You now know what \"y\" is equal to.\r<BR>\n" );
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document.write( "Next you will plug what \"y\" equals into the first equation( 3x-y=21)\r<BR>\n" );
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document.write( "So the new equation would look like this:\r<BR>\n" );
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document.write( "3x+2x-4=21\r<BR>\n" );
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document.write( "5x=25\r<BR>\n" );
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document.write( "x=5\r<BR>\n" );
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document.write( "Now find out what \"y\" equals.\r<BR>\n" );
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document.write( "y=-2x+4\r<BR>\n" );
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document.write( "y=-10+4\r<BR>\n" );
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document.write( "y=-6\r<BR>\n" );
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document.write( "The Check Step.\r<BR>\n" );
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document.write( "You now know that y=-6 and x=5\r<BR>\n" );
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document.write( "You will plug the numbers back into the first or second equation.\r<BR>\n" );
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document.write( "3x-y=21\r<BR>\n" );
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document.write( "3(5)-(-6)=21\r<BR>\n" );
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document.write( "15+6=21\r<BR>\n" );
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document.write( "21=21<BR>\n" );
document.write( " \r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );