document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1016897>Question 1016897</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It costs $3 a mile to go for a ride in a taxi. After 6 miles, it then costs $5.25 per mile. Write the particular equation expressing cost (c) in miles (d).\r<BR>\n" );
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document.write( "This is supposed to be written as ONE equation?! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #633256 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=633256\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let c = total cost.<BR>\n" );
document.write( "let d = number of miles.\r<BR>\n" );
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document.write( "it cost 3.00 per mile up to 6 miles.\r<BR>\n" );
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document.write( "it costs 5.25 per mile after 6 miles.\r<BR>\n" );
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document.write( "as a split equation, this would be:\r<BR>\n" );
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document.write( "c = 3.00 * d, 0 <= d <= 6<BR>\n" );
document.write( "c = 5.25 * d - 13.5, d > 6\r<BR>\n" );
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document.write( "i don't believe it can be modeled as one equation.<BR>\n" );
document.write( "it's more than likely 2 equations.<BR>\n" );
document.write( "i call these split equations.<BR>\n" );
document.write( "i think they're also called partial equations.<BR>\n" );
document.write( "different equations take care of different parts of the problem.\r<BR>\n" );
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document.write( "in the real world, problems like this are usually solved by computer.<BR>\n" );
document.write( "the computer contains logic that can differentiate between whether or not the number of miles traveled was less than or equal to 6, or greater than 6.\r<BR>\n" );
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document.write( "an example of pseudo code (computer code written in english) shows you what i mean.\r<BR>\n" );
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document.write( "if the number of miles traveled is less than or equal to 6, charge 3 dollars per mile.<BR>\n" );
document.write( "if the number of miles traveled is greater than 6, charge 5.25 per mile and subtract 13.5 dollars from the total.\r<BR>\n" );
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document.write( "13.5 is equal to 6 * 2.25.<BR>\n" );
document.write( "that's the difference between 5.25 dollars per mile and 3 dollars per mile.<BR>\n" );
document.write( "so, the first 6 miles are charged at 5.25 dollars per mile minus 2.25 dollars per mile for a net charge of 3 dollars per mile.<BR>\n" );
document.write( "after 6 miles, the full 5.25 dollars per mile is charged.\r<BR>\n" );
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document.write( "here's what would happen.\r<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "miles traveled   cost\r\n" );
document.write( "0                 3 * 0 = 0\r\n" );
document.write( "1                 3 * 1 = 3\r\n" );
document.write( "2                 3 * 2 = 6\r\n" );
document.write( "3                 3 * 3 = 9\r\n" );
document.write( "4                 3 * 4 = 12\r\n" );
document.write( "5                 3 * 5 = 15\r\n" );
document.write( "6                 3 * 6 = 18\r\n" );
document.write( "7                 5.25 * 7 - 13.5 = 23.25\r\n" );
document.write( "8                 5.25 * 8 - 13.5 = 28.5\r\n" );
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document.write( "when you go 7 miles, it's 3 dollars per mile for the first 6 plus 5.25 for the next mile which is equal to 18 + 5.25 = 23.5 dollars.\r<BR>\n" );
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document.write( "when you go 8 miles, it's 3 dollars per mile for the first 6 plus 5.25 for the next 2 miles which is equal to 18 + 2 * 5.25 = 18 + 10.5 = 28.5.\r<BR>\n" );
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document.write( "the algebraic formula that takes that into account was shown above and is reproduced here:\r<BR>\n" );
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document.write( "c = 3.00 * d, 0 <= d <= 6<BR>\n" );
document.write( "c = 5.25 * d - 13.5, d > 6\r<BR>\n" );
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document.write( "these formulas say:\r<BR>\n" );
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document.write( "charge 3 dollars per mile when the number of miles is less and or equal to 6.<BR>\n" );
document.write( "charge 5.25 dollars per mile and then subtract 13.5 dollars from the total when the number of miles is greater than 6.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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