document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=272377>Question 272377</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solving using the substitution method: \r<BR>\n" );
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document.write( "8x - 5y = -47<BR>\n" );
document.write( "4x + 3y = -7\r<BR>\n" );
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document.write( "I got some help from the site, but I dont know how it derived to that answer. When doing it long hand, I couldn't get the same results.\r<BR>\n" );
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document.write( "Expressing x as a function of y (from the first equation) x = (-47 +5y)/8<BR>\n" );
document.write( "Substituting this expression into the second equation:\r<BR>\n" );
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document.write( "4(-47-5y)/8+3y = -7\r<BR>\n" );
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document.write( "Simplifying this expression:\r<BR>\n" );
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document.write( "44y = 132 or y = 3\r<BR>\n" );
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document.write( "Now, substituting y = 3 back into the x expressed as a function of y:<BR>\n" );
document.write( "x = (-47+5y)/8 = -4<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 #199269 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=199269\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 8x - 5y = -47<BR>\n" );
document.write( "8X=5Y-47<BR>\n" );
document.write( "X=(5Y-47)/8<BR>\n" );
document.write( "4x + 3y = -7<BR>\n" );
document.write( "4(5Y-47)/8+3Y=-7<BR>\n" );
document.write( "(20Y-188)/8+3Y=-7<BR>\n" );
document.write( "(20Y-188+3Y*8)/8=-7<BR>\n" );
document.write( "20Y-188+24Y=-56<BR>\n" );
document.write( "44Y=-56+188<BR>\n" );
document.write( "44Y=132<BR>\n" );
document.write( "Y=132/44<BR>\n" );
document.write( "Y=3 ANS.<BR>\n" );
document.write( "X=(5*3-47)/8<BR>\n" );
document.write( "X=(15-47)/8<BR>\n" );
document.write( "X=-32/8<BR>\n" );
document.write( "X=-4 ANS.<BR>\n" );
document.write( "PROOF:<BR>\n" );
document.write( "4*-4+3*3=-7<BR>\n" );
document.write( "-16+9=-7<BR>\n" );
document.write( "-7=-7<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );