I have used the equation

s=ut + 1/2atsquared

This is Motion

Posted Fri 18th October, 2013 @ 12:27 by

Artsy444
You plug the values into s=ut+1/2at^2. You will be left with 20=5.5t+2t^2.

therefore: 2t^2+5.5t-20=0

Using the quadratic formula you can find your values for t. (Ignore negative value)

Answered Tue 10th December, 2013 @ 08:02 by

Ragnaros the Firelord