document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1099057>Question 1099057</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dog Years.  A dog's life span is typically much shorter than that of a human. Age equivalents for dogs and humans are listed in the table below.\r<BR>\n" );
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document.write( "Age of Dog, x (in years)<BR>\n" );
document.write( "0.25<BR>\n" );
document.write( "0.5<BR>\n" );
document.write( "1<BR>\n" );
document.write( "2<BR>\n" );
document.write( "4<BR>\n" );
document.write( "6<BR>\n" );
document.write( "8<BR>\n" );
document.write( "10<BR>\n" );
document.write( "14<BR>\n" );
document.write( "18<BR>\n" );
document.write( "21\r<BR>\n" );
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document.write( "Human Age, h (x) (in years) <BR>\n" );
document.write( "5<BR>\n" );
document.write( "10<BR>\n" );
document.write( "15<BR>\n" );
document.write( "24<BR>\n" );
document.write( "32<BR>\n" );
document.write( "40<BR>\n" );
document.write( "48<BR>\n" );
document.write( "56<BR>\n" );
document.write( "72<BR>\n" );
document.write( "91<BR>\n" );
document.write( "106\r<BR>\n" );
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document.write( "a) Use a graphing calculator to fit linear and cubic functions to the data. Which function has the better fit?\r<BR>\n" );
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document.write( "b) Using the function from part (a), estimate the equivalent human age for dogs that are 5, 10, and 15 years old.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #713578 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=713578\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Linear is y=4.55x+10.31 r^2 of 0.997<BR>\n" );
document.write( "Cubic is y=0.103x^3-.34x^2+7.40x+6.62 and r^2 is 0.997<BR>\n" );
document.write( "when x=5, y=48.0<BR>\n" );
document.write( "x=10, y=112.62<BR>\n" );
document.write( "x=15, y=388.745<BR>\n" );
document.write( "cubics become very large as x increases modestly\r<BR>\n" );
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document.write( "linear had almost same fit<BR>\n" );
document.write( "x=5<BR>\n" );
document.write( "33.06<BR>\n" );
document.write( "x=10<BR>\n" );
document.write( "55.86<BR>\n" );
document.write( "x=15<BR>\n" );
document.write( "78.56<BR>\n" );
document.write( "so while the R^2 is slightly better for the cubic function, the linear approximates everything much better.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );