document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1057063>Question 1057063</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please solve this system using substitution.<BR>\n" );
document.write( "   4x-y=5<BR>\n" );
document.write( "   4x+4y=-4\r<BR>\n" );
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document.write( "Thank you,<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 #672186 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=672186\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 4x-y = 5   (eq 1)<BR>\n" );
document.write( "4x+4y = -4  (eq 2)\r<BR>\n" );
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document.write( "From (eq 1):  y=4x-5<BR>\n" );
document.write( "Substitute this expression for 'y' in eq 2:\r<BR>\n" );
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document.write( "4x+4(4x-5) = -4<BR>\n" );
document.write( "4x+16x-20 = -4<BR>\n" );
document.write( "20x = 16<BR>\n" );
document.write( "x = 16/20 = 4/5,   y = 4(4/5) - 5 = -9/5\r<BR>\n" );
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document.write( "—<BR>\n" );
document.write( "Ans:  x = 4/5,  y = -9/5<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "(eq1)  4x-y = 4(4/5)-(-9/5) = 25/5 = 5  (ok)<BR>\n" );
document.write( "(eq2)  4x+4y = 4(4/5) + 4(-9/5) = 16/5-36/5 = -20/5 = -4  (ok)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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