document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=791782>Question 791782</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What would be the easiest way to solve this problem ? The only known value is that z=9\r<BR>\n" );
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document.write( "x + Y + Z = 14<BR>\n" );
document.write( "x - 2y = -4<BR>\n" );
document.write( "Z = 9 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #479725 by </B><A HREF=/tutors/aboutme.mpl?userid=DrBeeee><B>DrBeeee(684)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=DrBeeee><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=479725\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Given<BR>\n" );
document.write( "(1) z = 9<BR>\n" );
document.write( "(2) x + y + z = 14<BR>\n" );
document.write( "(3) x - 2y = -4<BR>\n" );
document.write( "Substitute z of (1) into (2) and get<BR>\n" );
document.write( "(4) x + y + 9 = 14 or<BR>\n" );
document.write( "(5) x + y = 5<BR>\n" );
document.write( "Now you have two equations, (5) and (3) to solve simultaneously for x and y. Use the following steps;<BR>\n" );
document.write( "Subtract equation (3) from equation (5) as follows to get<BR>\n" );
document.write( "(6) (x+y) - (x-2y) = 5 - (-4) or<BR>\n" );
document.write( "(7) 3y = 9 or<BR>\n" );
document.write( "(8) y = 3<BR>\n" );
document.write( "Using (2) we get<BR>\n" );
document.write( "(9) x = 14 - 9 - 3 or<BR>\n" );
document.write( "(10) x = 2<BR>\n" );
document.write( "Let's check the values with (1), (2) and (3).<BR>\n" );
document.write( "Is (9 = 9)? Yes<BR>\n" );
document.write( "Is (2 + 3 + 9 = 14)?<BR>\n" );
document.write( "Is (14 = 14)? Yes<BR>\n" );
document.write( "Is (2 - 2*3 = -4)?<BR>\n" );
document.write( "Is (2 - 6 = -4)?<BR>\n" );
document.write( "Is (-4 = -4)? Yes<BR>\n" );
document.write( "Answer: {x,y,z} = {2,3,9). The easy way!<BR>\n" );
document.write( "PS Don't mix upper case and lower case letters, y and Y, - they are different variables in mathematics and passwords. </SPAN>\n" );
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