document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=32212>Question 32212</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is the problem that I have trouble solving. I have an idea of how to solve it but I am not sure where to beign to find the x cooridinates. \r<BR>\n" );
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document.write( "You are riding on a roller coaster whose path can be modeled by<BR>\n" );
document.write( "y=.005x2(squared)-2x+200<BR>\n" );
document.write( "where x and y are measured in feet. When t=0 sec, you are at the point (0,200) going downhill. <BR>\n" );
document.write( "a. when t=4 sec, the y coordinate of your locations is 32. What is the x coordinate? <BR>\n" );
document.write( "b. when t=4.23sec, the y coordinate of your location is 18. What is the y coordinate?<BR>\n" );
document.write( "c.Use pythagorean theorem to approximate the lenght of the track between the two points. <BR>\n" );
document.write( "d. what was the average speed betweem the two points?\r<BR>\n" );
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document.write( "Thanks.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #18769 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=18769\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y=0.005x^2-2x+200<BR>\n" );
document.write( "a)32=0.005x^2-2x+200<BR>\n" );
document.write( "   0=0.005x^2-2x+168<BR>\n" );
document.write( "Graphing this I find x=120, giving the point (120,32)<BR>\n" );
document.write( "b)18=0.005x^2 etc.<BR>\n" );
document.write( "  0 =0.005x^2-2x+182<BR>\n" );
document.write( "Graphing this I find x=140, giving the point (140,18)<BR>\n" );
document.write( "c) d=sqrt[(32-18)^2 + (120-140)^2]= 24.4 ft<BR>\n" );
document.write( "d) The average is the distance divided by the time change:<BR>\n" );
document.write( " ave.= 24.4 ft/ (0.23) sec. = 106.09 ft./sec.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "stan H.<BR>\n" );
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