Can you help me solve this application? 
A particle moves along a straight line 
according to the formula s=2t² + t - 6, where 
s represents the distance in inches from the 
beginning point, and t represents the time 
in seconds. Find the time (to the nearest 
hundredth of a second when the particle is 
5 inches from the beginning point. 
Thanks
Elizabeth

s = 2t² + t - 6

Just substitute 5 for s and solve for t:

5 = 2t² + t - 6

0 = 2t² + t - 11

That won't factor:

      2t² + t - 11 = 0

So we use the quadratic formula:
                  ______ 
            -b ± Öb²-4ac
        x = —————————————
                2a 

where a = 2; b = 1; c = -11; x = t

                     ______________ 
             -(1) ± Ö(1)²-4(2)(-11)
        t = ————————————————————————
                     2(2) 
                   _____ 
             -1 ± Ö1+88
        t = —————————————
                 4

                   __ 
             -1 ± Ö89
        t = ——————————
                 4

                      
Using the +, we get t about 2.108495283 seconds, 
or about 2.11 seconds, to the nearest hundredth
of a second.
                      
Using the -, we get a negative value, which we discard.

Edwin