document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=190088>Question 190088</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A community theater sells about 150 tickets to a play each week when it charges $20 per ticket. For each $1 decrease in price, about 10 more tickets per week are sold. The theater has fixed expenses of $1500 per week.\r<BR>\n" );
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document.write( "Write a model: write a verbal model and a quadratic function to represent the theater's weekly profit.\r<BR>\n" );
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document.write( "What i did is this, but I am not sure if I am right:<BR>\n" );
document.write( "y=(-x+20)(10x+150)-1500<BR>\n" );
document.write( "y=-10x^2-150x+200x+3000-1500<BR>\n" );
document.write( "y=-10x^2+50x+1500\r<BR>\n" );
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document.write( "I really don't understand how to create equations out of word problems like this. I really appreciate the help.. Thank You ! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #142682 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=142682\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Garamond\" size=\"+2\">\r<BR>\n" );
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document.write( "Yep, that's exactly right as long as you realize that your independent variable represents the price <i><b>differential</b></i>.  In other words, the actual price of a ticket is 20 - <i>x</i>.\r<BR>\n" );
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document.write( "That means you have some restrictions on the domain of your function.  For one thing, <i>x</i> has to be less than 20 (unless the play is <i><b>so</b></i> bad they have to pay people to attend) and <i>x</i> has to be less than 35 or they would sell zero tickets.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi} + 1 = 0\"><BR>\n" );
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