What is the total time in the air for the parachutist's jump?

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Hey could someone explain to me this problem because i tried every single variation of the rules i learned in class, v = delta d/ delta t a= delta v/ delta t ect.. and i kept getting the wrong answer.

A parachustist jumps from an airplane and freely falls y=53.2 m before opening his parachute. Thereafter, he decelerates at a=2.00 m/s2. As he reaches the ground, his speed is 3.23 m/s. How long was the parachutist in the air?
 
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First step - free fall - requires you to find time needed to cover distance while accelerating at g. Second step - slowing down - requires you to find time necessary to slow down from the final speed of free fall (you will have to calculate it from time and g) to the landing speed.