document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=4990>Question 4990</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve using the substitution method.\r<BR>\n" );
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document.write( "#1\r<BR>\n" );
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document.write( "y=5-x<BR>\n" );
document.write( "3x-4y=-20\r<BR>\n" );
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document.write( "#2\r<BR>\n" );
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document.write( "x+2y=6<BR>\n" );
document.write( "2x+3y=8\r<BR>\n" );
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document.write( "#3\r<BR>\n" );
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document.write( "3x+y=1<BR>\n" );
document.write( "x=2y+5\r<BR>\n" );
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document.write( "#4\r<BR>\n" );
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document.write( "x+y=6<BR>\n" );
document.write( "y=3-2x\r<BR>\n" );
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document.write( "#5\r<BR>\n" );
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document.write( "s+t=5<BR>\n" );
document.write( "s=13-3t\r<BR>\n" );
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document.write( "#6\r<BR>\n" );
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document.write( "x-y=4<BR>\n" );
document.write( "y=2-x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #3722 by </B><A HREF=/tutors/aboutme.mpl?userid=nidz><B>nidz(2)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nidz><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=3722\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> #1 <BR>\n" );
document.write( "y=5-x<BR>\n" );
document.write( "3x-4y=-20 \r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "y=5-x      ..eq(i)<BR>\n" );
document.write( "3x-4y=-20  ..eq(ii)\r<BR>\n" );
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document.write( "substitute the value of y from eq(i) in eq(ii),<BR>\n" );
document.write( "then eq(ii) will be<BR>\n" );
document.write( "3x-4(5-x)=-20<BR>\n" );
document.write( "3x-20-4x=-20<BR>\n" );
document.write( "-20-x=-20<BR>\n" );
document.write( "x=-20+20<BR>\n" );
document.write( "x=0\r<BR>\n" );
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document.write( "#2 <BR>\n" );
document.write( "x+2y=6<BR>\n" );
document.write( "2x+3y=8 \r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "x+2y=6  ..eq(i)<BR>\n" );
document.write( "2x+3y=8 ..eq(ii)\r<BR>\n" );
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document.write( "from eq(i),<BR>\n" );
document.write( "x=6-2y\r<BR>\n" );
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document.write( "substitute the value of x in eq(ii),<BR>\n" );
document.write( "then eq(ii) will be<BR>\n" );
document.write( "2(6-2y)+3y=8<BR>\n" );
document.write( "12-4y+3y=8<BR>\n" );
document.write( "12-y=8<BR>\n" );
document.write( "y=12-8<BR>\n" );
document.write( "y=4\r<BR>\n" );
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document.write( "#3 <BR>\n" );
document.write( "3x+y=1<BR>\n" );
document.write( "x=2y+5 \r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "3x+y=1  ..eq(i)<BR>\n" );
document.write( "x=2y+5  ..eq(ii)\r<BR>\n" );
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document.write( "substitute the value of x from eq(ii) in eq(i),<BR>\n" );
document.write( "then eq(i)will be<BR>\n" );
document.write( "3(2y+5)+y=1<BR>\n" );
document.write( "6y+15+y=1<BR>\n" );
document.write( "7y+15=1<BR>\n" );
document.write( "7y=1-15<BR>\n" );
document.write( "7y=-14<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-14%2F7 ALIGN=MIDDLE  ALT=\"y=-14%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "y=-2\r<BR>\n" );
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document.write( "#4 <BR>\n" );
document.write( "x+y=6<BR>\n" );
document.write( "y=3-2x\r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "x+y=6  ..eq(i)<BR>\n" );
document.write( "y=3-2x ..eq(ii)\r<BR>\n" );
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document.write( "substitute the value of y from eq(ii) in eq(i)<BR>\n" );
document.write( "then eq(i) will be<BR>\n" );
document.write( "x+(3-2x)=6<BR>\n" );
document.write( "x+3-2x=6<BR>\n" );
document.write( "3-x=6<BR>\n" );
document.write( "x=3-6<BR>\n" );
document.write( "x=-3\r<BR>\n" );
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document.write( "#5 <BR>\n" );
document.write( "s+t=5<BR>\n" );
document.write( "s=13-3t\r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "s+t=5   ..eq(i)<BR>\n" );
document.write( "s=13-3t .eq(ii)\r<BR>\n" );
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document.write( "substitute the value of s from eq(ii) in eq(i)<BR>\n" );
document.write( "(13-3t)+t=5<BR>\n" );
document.write( "13-2t=5<BR>\n" );
document.write( "13-5=2t<BR>\n" );
document.write( "8=2t<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2F2=t ALIGN=MIDDLE  ALT=\"8%2F2=t\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t=4\r<BR>\n" );
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document.write( "#6 <BR>\n" );
document.write( "x-y=4<BR>\n" );
document.write( "y=2-x\r<BR>\n" );
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document.write( "sol:<BR>\n" );
document.write( "let,<BR>\n" );
document.write( "x-y=4 ..eq(i)<BR>\n" );
document.write( "y=2-x ..eq(ii)\r<BR>\n" );
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document.write( "substitute y in eq(i)<BR>\n" );
document.write( "x-(2-x)=4<BR>\n" );
document.write( "x-2+x=4<BR>\n" );
document.write( "2x-2=4<BR>\n" );
document.write( "2x=4+2<BR>\n" );
document.write( "2x=6<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=6%2F2 ALIGN=MIDDLE  ALT=\"x=6%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x=3 </SPAN>\n" );
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