document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=23140>Question 23140</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having problems with solving equations.  The following are equations and it's methods that I don't seem to understand.  Thank you for your assistance!\r<BR>\n" );
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document.write( "Solve using the addition (elimination) method.<BR>\n" );
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document.write( "2x + 3y = -16<BR>\n" );
document.write( "5x-10y=30\r<BR>\n" );
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document.write( "Solve using the addition (elimination) method<BR>\n" );
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document.write( "2y - 8 = -2x - 8x<BR>\n" );
document.write( "8x - 3y = 31 + y\r<BR>\n" );
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document.write( "Solve using the substitution method<BR>\n" );
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document.write( "x = 3y + 7<BR>\n" );
document.write( "x = 2y - 1\r<BR>\n" );
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document.write( "Solve using the substitution method<BR>\n" );
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document.write( "4x + 3y = 0<BR>\n" );
document.write( "2x - y = 0<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 #11620 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon%21><B>stanbon!(97)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon%21><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=11620\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Elimination:<BR>\n" );
document.write( "1st: 2x+3y=-16<BR>\n" );
document.write( "2nd: 5x-10y=30<BR>\n" );
document.write( "Multiply 1st by 5 and 2nd by 2 to get the following:<BR>\n" );
document.write( "1st: 10x+15y=-80<BR>\n" );
document.write( "2nd: 10x-20y=60<BR>\n" );
document.write( "Now subtract the 2nd from the 1st to eliminate the x's:<BR>\n" );
document.write( "    35y = -140<BR>\n" );
document.write( "      y =  -4<BR>\n" );
document.write( "Substitute that value of \"y\" into the original 1st<BR>\n" );
document.write( "equation to solve for \"x\":<BR>\n" );
document.write( "  2x+3(-4)= -16<BR>\n" );
document.write( "  2x-12 = -16<BR>\n" );
document.write( "      x = -2<BR>\n" );
document.write( "Check this answer of x=-2 and y=-4 in the 2nd original equation:<BR>\n" );
document.write( "  5(-2)-10(-4)= 30<BR>\n" );
document.write( "  -10+40 = 30<BR>\n" );
document.write( "      30 = 30\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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