document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=96139>Question 96139</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534954146/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> When a popular brand of CD player is priced at $300 per unit, a store sells 15 units per week.Each time the price is reduced by $10, however, the sale increases by two per week. What selling price will result in weekly revenues of $7000?\r<BR>\n" );
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document.write( "Can anyone help me with this? I am not sure about the set up. 300-10x +2 = 7000?<BR>\n" );
document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #69992 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=69992\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> your equation is close ... for every $10 price reduction, unit sales increase by 2\r<BR>\n" );
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document.write( "(300-10x)(15+2x)=7000 ... 4500+450x-20x^2=7000 ... -2500+450x-20x^2=0\r<BR>\n" );
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document.write( "rearranging terms and dividing by -10 gives 2x^2-45x+250=0 ... factoring gives (2x-25)(x-10)=0\r<BR>\n" );
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document.write( "so x=10 and x=12.5 ... giving a selling price of 300-10(10) or $200 \r<BR>\n" );
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document.write( "even though 12.5 is a solution to the equation; from the way the problem is stated, it looks like only integer values are valid </SPAN>\n" );
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