document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=314880>Question 314880</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help on solving by linear equation.<BR>\n" );
document.write( "4x-5y=20 and 5x+5y=70 I need to show work. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #225227 by </B><A HREF=/tutors/aboutme.mpl?userid=CharlesG2><B>CharlesG2(834)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=CharlesG2><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=225227\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I need help on solving by linear equation.<BR>\n" );
document.write( "4x-5y=20 and 5x+5y=70 I need to show work.\r<BR>\n" );
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document.write( "there are a few ways you can do this, solving for y on both and then setting equations equal is one, matrixes is another, elimination and substitution is yet another\r<BR>\n" );
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document.write( "4x -5y = 20<BR>\n" );
document.write( "5x +5y = 70 (notice the coefficients on the y's, they are opposites, add the 2 equations together)<BR>\n" );
document.write( "9x = 90<BR>\n" );
document.write( " x = 10, we now know x<BR>\n" );
document.write( "subsitute x into one of the equations and solve for y<BR>\n" );
document.write( "4(10) - 5y = 20<BR>\n" );
document.write( "40 - 5y = 20<BR>\n" );
document.write( "-5y = -20<BR>\n" );
document.write( "y = 4<BR>\n" );
document.write( "we could have used the other equation as well<BR>\n" );
document.write( "5(10) + 5y = 70<BR>\n" );
document.write( "50 + 5y = 70<BR>\n" );
document.write( "5y = 20<BR>\n" );
document.write( "y = 4<BR>\n" );
document.write( " </SPAN>\n" );
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