Question 64359: Can you help me solve this application?
A particle moves along a straight line according to the formula s=2t^2+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 incesh from the beginning point.
Thanks
Elizabeth
Answer by Edwin McCravy(20059) (Show Source):
You can put this solution on YOUR website! 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
|
|
|