document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1073271>Question 1073271</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A textbook store sold a combined total of 268 psychology and history textbooks in a week. <BR>\n" );
document.write( "The number of history textbooks sold was 58 less than the number of psychology textbooks sold. <BR>\n" );
document.write( "How many textbooks of each type were sold?<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 #688107 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=688107\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x = number of psychology books sold.<BR>\n" );
document.write( "let y = number of history books sold.\r<BR>\n" );
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document.write( "a total of 368 books were sold.\r<BR>\n" );
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document.write( "x + y = 268\r<BR>\n" );
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document.write( "the number of history books sold was 58 less than the number of psychology books sold.\r<BR>\n" );
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document.write( "y = x - 58\r<BR>\n" );
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document.write( "you have 2 equations that need to be solved simultaneously.\r<BR>\n" );
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document.write( "they are:\r<BR>\n" );
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document.write( "x + y = 268<BR>\n" );
document.write( "y = x - 58\r<BR>\n" );
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document.write( "since y = x - 58, then replace y in the first equation with x - 58 to get:\r<BR>\n" );
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document.write( "x + (x - 58) = 268\r<BR>\n" );
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document.write( "remove parentheses to get x + x - 58 = 268.\r<BR>\n" );
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document.write( "combine like terms to get 2x - 58 = 268.\r<BR>\n" );
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document.write( "add 58 to both sides to get 2x = 326.\r<BR>\n" );
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document.write( "divide both sides by 2 to get x = 163.\r<BR>\n" );
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document.write( "since x + y = 268, then y = 268 - 163 = 105\r<BR>\n" );
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document.write( "the number of psychology books sold is 163.<BR>\n" );
document.write( "the number of history books sold is 105.\r<BR>\n" );
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document.write( "163 - 105 = 58.\r<BR>\n" );
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document.write( "there were 58 less history books sold than psychology books.\r<BR>\n" );
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