document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=107513>Question 107513</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am trying to help my daughter with her homework, but since I have no idea what I am doing I hope that having the answer will help me out:\r<BR>\n" );
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document.write( "Cost of owning a car problem:  The number of dollars per month it costs you to own a car is a function of the number of miles per month you drive it.  Based on information in an issue of Time magazine, the cost varies linearly with the distance and is $376 per month for 400 miles per month and $572 per month for 1800 miles per month.\r<BR>\n" );
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document.write( "a)  Write the particular equation expressing cost in terms of distance.<BR>\n" );
document.write( "b)  Predict the monthly cost if you drive 500, 1000, 2000 miles per month.<BR>\n" );
document.write( "c)  About how far could you drive in a month without exceeding a monthly cost of $600?<BR>\n" );
document.write( "d)  What does the slope reprsent?<BR>\n" );
document.write( "e)  List all the resons you can think of to explain why the dollars per month intercept is grater than zero.<BR>\n" );
document.write( "f)  Sketch and label the graph.\r<BR>\n" );
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document.write( "Thank you in advance for any help you can give me.<BR>\n" );
document.write( "Brian </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #78309 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=78309\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> using the two cost & distance figures, you cand find the \"cost per mile\" (slope of the line)\r<BR>\n" );
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document.write( "(572-376)/(1800-400)=196/1400=.14\r<BR>\n" );
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document.write( "if it costs 14 cents per mile then 376-(.14*400) or 320 represents the \"fixed costs\"\r<BR>\n" );
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document.write( "the equation is (cost)=.14(miles)+320\r<BR>\n" );
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document.write( "for b) and c) just plug the numbers into the equation\r<BR>\n" );
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document.write( "e) is stuff like car payments - that are NOT milage related </SPAN>\n" );
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