document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=884682>Question 884682</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Brian's revenue R in dollars from the sale of x baseball souvenirs is determined by the formula R=20x-x^2. His cost C in dollars is given by the formula C=-19x+140. For what values of x is Brian's profit positive? Write your answer in complete sentences.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #534566 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=534566\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Brian's revenue R in dollars from the sale of x baseball souvenirs is determined by the formula R=20x-x^2. His cost C in dollars is given by the formula C=-19x+140. For what values of x is Brian's profit positive? Write your answer in complete sentences.<BR>\n" );
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document.write( "profit=revenue-cost=(20x-x^2)-(-19x+140)<BR>\n" );
document.write( "P(x)=20x-x^2+19x-140>0<BR>\n" );
document.write( "P(x)=-x^2+39x-140>0<BR>\n" );
document.write( "P(x)=-(x^2-39x+140>0<BR>\n" );
document.write( "P(x)=-(x-4)(x-35)>0<BR>\n" );
document.write( "number line:<BR>\n" );
document.write( "<...-...4.....+....35....-.....><BR>\n" );
document.write( "what values of x is Brian's profit positive?  (4,35), that is, all values of x between 4 and 35 </SPAN>\n" );
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