document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=133136>Question 133136</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The formula d = 0.05s^2 + 1.1s estimates the minimum stopping distance d in feet for a car traveling s miles per hour.\r<BR>\n" );
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document.write( "a. a car traveling at 60 miles per hour, how many feet does this car need to safely stop?\r<BR>\n" );
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document.write( "b. What is the maximum speed a car can be traveling if it has only 50 feet to stop?\r<BR>\n" );
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document.write( "Thank you for your help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #97355 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley71><B>checkley71(8403)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley71><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=97355\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=.05s^2+1.1s<BR>\n" );
document.write( "d=.05*60^2+1.1*60<BR>\n" );
document.write( "d=.05*3600+66<BR>\n" );
document.write( "d=180+66<BR>\n" );
document.write( "d=246 feet to stop when traveling 60 mph.<BR>\n" );
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document.write( "50=.05s^2+1.1s <BR>\n" );
document.write( ".05s^2+1.1s-50=0<BR>\n" );
document.write( "using the quadratic equation:<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > we get:<BR>\n" );
document.write( "s=(-1.1+-sqrt[1.1^2-4*.05*-50])/2*.05<BR>\n" );
document.write( "s=(-1.1+-sqrt[1.21+10])/.1<BR>\n" );
document.write( "s=(-1.1+-sqrt11.21)/.1<BR>\n" );
document.write( "s=(-1.1+-3.348)/.1<BR>\n" );
document.write( "s=(-1.1+3.348)/.1<BR>\n" );
document.write( "s=(-1.1+3.348)/.1<BR>\n" );
document.write( "s=2.248/.1<BR>\n" );
document.write( "s=22.48 mph is the max speed for a 50 foot stopping distance. </SPAN>\n" );
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