document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=863301>Question 863301</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have exams coming up soon but I can't solve these revision questions on simultaneous equations! Can you please explain to me how to solve:\r<BR>\n" );
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document.write( "4a+2b=10<BR>\n" );
document.write( "9a=27-3b\r<BR>\n" );
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document.write( "And \r<BR>\n" );
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document.write( "3x-4y=10<BR>\n" );
document.write( "2x-y=5\r<BR>\n" );
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document.write( "Thank you so much if you answer this! I'm trying to be eligible for further maths in my GCSEs. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #520348 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=520348\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1)4a+2b=10<BR>\n" );
document.write( "9a=27-3b <BR>\n" );
document.write( "solve second equation for a<BR>\n" );
document.write( "a = 3 - b/3<BR>\n" );
document.write( "substitute for a in first equation<BR>\n" );
document.write( "4(3 - b/3) +2b = 10<BR>\n" );
document.write( "12 - 4b/3 + 6b/3 = 10<BR>\n" );
document.write( "2b/3 = -2<BR>\n" );
document.write( "2b = -6<BR>\n" );
document.write( "b = -3<BR>\n" );
document.write( "substitute for b in first equation<BR>\n" );
document.write( "4a-6 = 10<BR>\n" );
document.write( "4a = 16<BR>\n" );
document.write( "a = 4<BR>\n" );
document.write( "solution a = 4, b = -3<BR>\n" );
document.write( "2)3x-4y=10<BR>\n" );
document.write( "2x-y=5 <BR>\n" );
document.write( "solve second equation for y<BR>\n" );
document.write( "-y = 5 - 2x<BR>\n" );
document.write( "y = 2x - 5 <BR>\n" );
document.write( "now substitute for y in first equation<BR>\n" );
document.write( "3x - 4(2x - 5) = 10<BR>\n" );
document.write( "3x -8x + 20 = 10<BR>\n" );
document.write( "-5x = -10<BR>\n" );
document.write( "x = 2<BR>\n" );
document.write( "substitute for x in first equation<BR>\n" );
document.write( "6 - 4y = 10<BR>\n" );
document.write( "-4y = 4<BR>\n" );
document.write( "y = -1<BR>\n" );
document.write( "solution x = 2, y = -1<BR>\n" );
document.write( " </SPAN>\n" );
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