document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=246261>Question 246261</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have been working on this question for hours and my work doesn't add up right.  Can you please show me how i would work this problem out.\r<BR>\n" );
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document.write( " Free market. The equations S = 5000 + 200x and D = 9500 - 100x express the supply S and the demand D, respectively, for a popular compact disc brand in terms of its price x (in dollars). \r<BR>\n" );
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document.write( "             a) Graph the equations of the same coordinate system.<BR>\n" );
document.write( "             b) What happens to the supply as the price increases?<BR>\n" );
document.write( "             c) What happens to the demand as the price increases?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #179895 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=179895\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> S = 5000 + 200x<BR>\n" );
document.write( "D = 9500 - 100x\r<BR>\n" );
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document.write( "x is the price in dollars.<BR>\n" );
document.write( "S is the supply<BR>\n" );
document.write( "D is the demand\r<BR>\n" );
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document.write( "Looks like the supply goes up as the price goes up.\r<BR>\n" );
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document.write( "Looks like the demand goes down as the price goes up.\r<BR>\n" );
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document.write( "The graph of these equations would look like the following:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28600%2C600%2C-10%2C30%2C-1000%2C19000%2C5000%2B200x%2C9500-100x%29 ALIGN=MIDDLE  ALT=\"graph%28600%2C600%2C-10%2C30%2C-1000%2C19000%2C5000%2B200x%2C9500-100x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "a) Graph the equations of the same coordinate system.\r<BR>\n" );
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document.write( "             b) What happens to the supply as the price increases?\r<BR>\n" );
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document.write( "The supply goes up.\r<BR>\n" );
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document.write( "             c) What happens to the demand as the price increases?\r<BR>\n" );
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document.write( "The demand goes down.\r<BR>\n" );
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document.write( "There's an equilibrium point where the supply is the same as the demand.\r<BR>\n" );
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document.write( "That's where the graph of the two equations intersect.\r<BR>\n" );
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document.write( "You solve for that point by making the two equations equal to each other.\r<BR>\n" );
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document.write( "You get:\r<BR>\n" );
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document.write( "5000 + 200x = 9500 - 100x\r<BR>\n" );
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document.write( "add 100x to both sides of this equation and subtract 5000 from both sides of this equation to get:\r<BR>\n" );
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document.write( "200x + 100x = 9500 - 5000\r<BR>\n" );
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document.write( "combine like terms to get:\r<BR>\n" );
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document.write( "300x = 4500\r<BR>\n" );
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document.write( "divide both sides of this equation by 300 to get:\r<BR>\n" );
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document.write( "x = 4500/300 = 45/3 = 15\r<BR>\n" );
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document.write( "the graph confirms that.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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