document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1073378>Question 1073378</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A fruit grower use two types of fertilizer in his orange grove, brand A and brand B. Each bag of brand A contains 9 pounds of nitrogen and 5 pounds of phosphoric acid. Each bag of brand B contains 8 pound of nitrogen and 6 pounds of phosphoric acid. Test indicate that the grove needs 770 pounds of nitrogen and 490 pounds of phosphoric acid. How many bags of each brand should be used to provide the required amounts of nitrogen and phosphoric acid. \r<BR>\n" );
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document.write( "I set up the equation with this:<BR>\n" );
document.write( "9a + 8b=770\r<BR>\n" );
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document.write( "5a + 6b=490\r<BR>\n" );
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document.write( "I then took equation #2 and times it by 2, then subtracted equation #1 from equation #2... \r<BR>\n" );
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document.write( "Help at a loss..  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #688212 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52814)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=688212\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
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document.write( "You have this system\r\n" );
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document.write( "9a + 8b = 770      (1)\r\n" );
document.write( "5a + 6b = 490      (2)\r\n" );
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document.write( "Multiply eq(1) by 5 (both sides). Multiply eq(2) by 9 (both sides). You will get\r\n" );
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document.write( "45a + 40b = 3850   (1')\r\n" );
document.write( "45a + 54b = 4410   (2')\r\n" );
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document.write( "Now subtract eq(1') from eq(2'). You will get\r\n" );
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document.write( "54b - 40b = 4410 - 3850,   or\r\n" );
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document.write( "14b = 560   --->  b = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=560%2F14 ALIGN=MIDDLE  ALT=\"560%2F14\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 40.\r\n" );
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document.write( "From this point please complete the solution on your own.\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "The method I used is called the \"Elimination method\".\r<BR>\n" );
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document.write( "On solving systems of two linear equations in two unknowns (Algebra-I curriculum) see the lesson\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF= http://www.algebra.com/algebra/homework/coordinate/lessons/Solution-of-the-lin-system-of-two-eqns-by-the-Subst-method.lesson>Solution of the linear system of two equations in two unknowns by the Substitution method</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF= http://www.algebra.com/algebra/homework/coordinate/lessons/Solution-of-the-lin-syst-of-two-eqns-with-two-unknowns-Elimination-method.lesson>Solution of the linear system of two equations in two unknowns by the Elimination method</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/coordinate/lessons/Solution-of-the-lin-syst-of-two-eqns-with-two-unknowns-using-det.lesson>Solution of the linear system of two equations in two unknowns using determinant</A> \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/coordinate/lessons/Geom-interpret-of-the-lin-system-of-two-eqns-with-two-unknowns.lesson>Geometric interpretation of the linear system of two equations in two unknowns</A> \r<BR>\n" );
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document.write( "in this site.\r<BR>\n" );
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document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.\r<BR>\n" );
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document.write( "The referred lessons are the part of this online textbook under the topic \"<U>Systems of two linear equations in two unknowns</U>\".\r<BR>\n" );
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document.write( " </SPAN>\n" );
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