document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=947787>Question 947787</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this equation: Pack-Em-In Real Estate is building a new housing development. The more houses it builds, the less people will be willing to pay, due to the crowding and smaller lot sizes. In fact, if it builds 20 houses in this particular development, it can sell them for $640,000 each, but if it builds 70 houses, it will only be able to get $440,000 each. Obtain a linear demand equation (Let p be the price of a house and q the number of houses.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #578407 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=578407\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Plot <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+p+ ALIGN=MIDDLE  ALT=\"+p+\"   DISABLED_style= \"max-width:90%; height:auto;\" > on the vertical axis<BR>\n" );
document.write( "Plot <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+q+ ALIGN=MIDDLE  ALT=\"+q+\"   DISABLED_style= \"max-width:90%; height:auto;\" > on the horizontal axis<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "You are given the 2 points, ( q,p ):<BR>\n" );
document.write( "( 20, 64 )<BR>\n" );
document.write( "( 70, 44 ) <BR>\n" );
document.write( "( <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+p+ ALIGN=MIDDLE  ALT=\"+p+\"   DISABLED_style= \"max-width:90%; height:auto;\" > is scaled down by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1%2F10000+ ALIGN=MIDDLE  ALT=\"+1%2F10000+\"   DISABLED_style= \"max-width:90%; height:auto;\" > )<BR>\n" );
document.write( "-------------------------------------<BR>\n" );
document.write( "Use the general point-slope formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+%28+64+-+44+%29+%2F+%28+20+-+70+%29+ ALIGN=MIDDLE  ALT=\"+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+%28+64+-+44+%29+%2F+%28+20+-+70+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+20+%2F+%28-50%29+ ALIGN=MIDDLE  ALT=\"+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+20+%2F+%28-50%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+-2%2F5+ ALIGN=MIDDLE  ALT=\"+%28+y+-+44+%29+%2F+%28+x+-+70+%29+=+-2%2F5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5%2A%28+x+-+70+%29+ ALIGN=MIDDLE  ALT=\"+5%2A%28+x+-+70+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5%2A%28+y+-+44+%29+=+-2%2A%28+x+-+70+%29+ ALIGN=MIDDLE  ALT=\"+5%2A%28+y+-+44+%29+=+-2%2A%28+x+-+70+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5y+-+220+=+-2x+%2B+140+ ALIGN=MIDDLE  ALT=\"+5y+-+220+=+-2x+%2B+140+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5y+=+-2x+%2B+360+ ALIGN=MIDDLE  ALT=\"+5y+=+-2x+%2B+360+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+-%282%2F5%29%2Ax+%2B+72+ ALIGN=MIDDLE  ALT=\"+y+=+-%282%2F5%29%2Ax+%2B+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "( 20,64 )<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+-%282%2F5%29%2Ax+%2B+72+ ALIGN=MIDDLE  ALT=\"+y+=+-%282%2F5%29%2Ax+%2B+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+64+=+-%282%2F5%29%2A20+%2B+72+ ALIGN=MIDDLE  ALT=\"+64+=+-%282%2F5%29%2A20+%2B+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+64+=+-8+%2B+72+ ALIGN=MIDDLE  ALT=\"+64+=+-8+%2B+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+64+=+64+ ALIGN=MIDDLE  ALT=\"+64+=+64+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "You can check the other point<BR>\n" );
document.write( "Here's the plot:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+400%2C+400%2C+-10%2C+100%2C+-10%2C+80%2C+-%282%2F5%29%2Ax+%2B+72+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+400%2C+400%2C+-10%2C+100%2C+-10%2C+80%2C+-%282%2F5%29%2Ax+%2B+72+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );