document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=385320>Question 385320</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve <BR>\n" );
document.write( "x+4y=19<BR>\n" );
document.write( "5x+y+0\r<BR>\n" );
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document.write( "solve <BR>\n" );
document.write( "a-b=25<BR>\n" );
document.write( "3a+4b=4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #272616 by </B><A HREF=/tutors/aboutme.mpl?userid=texttutoring><B>texttutoring(324)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=texttutoring><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=texttutoring><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=272616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+4y=19<BR>\n" );
document.write( "5x+y+0\r<BR>\n" );
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document.write( "Let's solve this one by elimination method. Multiply the second equation by 4, then subtract it from the first equation:\r<BR>\n" );
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document.write( "x+4y = 19<BR>\n" );
document.write( "20x +4y = 0<BR>\n" );
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document.write( "-19x = 19\r<BR>\n" );
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document.write( "x= -1\r<BR>\n" );
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document.write( "Plug this value into either equation to find y:\r<BR>\n" );
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document.write( "5x+y = 0<BR>\n" );
document.write( "5(-1) + y = 0<BR>\n" );
document.write( "-5 + y = 0<BR>\n" );
document.write( "y = 5\r<BR>\n" );
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document.write( "So the solution is (-1,5) or x=-1, y=5.\r<BR>\n" );
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document.write( "Second question is weird because it has no nice answers. Are you supposed to write your answers as fractions or as decimals? I did it with fractions:\r<BR>\n" );
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document.write( "a-b=25<BR>\n" );
document.write( "3a+4b=4\r<BR>\n" );
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document.write( "Multiply the first equation by 3, then subtract.\r<BR>\n" );
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document.write( "3a - 3b = 75<BR>\n" );
document.write( "3a + 4b = 4<BR>\n" );
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document.write( "0 - 7b = 71\r<BR>\n" );
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document.write( "b = -71/7\r<BR>\n" );
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document.write( "Plug this into either equation to find a:\r<BR>\n" );
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document.write( "3a - 3(-71/7) = 75<BR>\n" );
document.write( "3a + 213/7 = 75<BR>\n" );
document.write( "3a = 75- 213/7<BR>\n" );
document.write( "3a = 312/7<BR>\n" );
document.write( "a = 312/21<BR>\n" );
document.write( "a = 104/7 </SPAN>\n" );
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