document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206099>Question 1206099</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A textbook store sold a combined total of 215 psychology and history textbooks in a week. The number of psychology textbooks sold was 57 more than the number of history textbooks sold. How many textbooks of each type were sold? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #843319 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20849)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=843319\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
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document.write( "let psychology textbooks be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p ALIGN=MIDDLE  ALT=\"p\"   DISABLED_style= \"max-width:90%; height:auto;\" > and history textbooks <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "if the store sold a combined total of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=215 ALIGN=MIDDLE  ALT=\"215\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we have \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%2Bh=215 ALIGN=MIDDLE  ALT=\"p%2Bh=215\"   DISABLED_style= \"max-width:90%; height:auto;\" >....eq.1\r<BR>\n" );
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document.write( "if the number of psychology textbooks sold was <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=57 ALIGN=MIDDLE  ALT=\"57\"   DISABLED_style= \"max-width:90%; height:auto;\" > more than the number of history textbooks sold, we have \r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=h%2B57 ALIGN=MIDDLE  ALT=\"p=h%2B57\"   DISABLED_style= \"max-width:90%; height:auto;\" >...eq.2\r<BR>\n" );
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document.write( "substitute  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p ALIGN=MIDDLE  ALT=\"p\"   DISABLED_style= \"max-width:90%; height:auto;\" > in eq.1\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%2B57%2Bh=215 ALIGN=MIDDLE  ALT=\"h%2B57%2Bh=215\"   DISABLED_style= \"max-width:90%; height:auto;\" >....eq.1\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2h=215-57 ALIGN=MIDDLE  ALT=\"2h=215-57\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2h=158 ALIGN=MIDDLE  ALT=\"2h=158\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=79 ALIGN=MIDDLE  ALT=\"h=79\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "go to eq.2, substitute <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=79%2B57 ALIGN=MIDDLE  ALT=\"p=79%2B57\"   DISABLED_style= \"max-width:90%; height:auto;\" >...eq.2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=136 ALIGN=MIDDLE  ALT=\"p=136\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=136 ALIGN=MIDDLE  ALT=\"136\"   DISABLED_style= \"max-width:90%; height:auto;\" > psychology and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=79 ALIGN=MIDDLE  ALT=\"79\"   DISABLED_style= \"max-width:90%; height:auto;\" > history textbooks were sold\r<BR>\n" );
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document.write( " </SPAN>\n" );
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