An acrobat can safely land on the ground at speeds up to 15 m/s. what is the greatest height from which the acrobat can fall?

I know you need to use too formulas but mi lost as to what I can do with speed to find the distance..

the given formulas are v = gt df = gt^2/2 t = sqr 2df/g

Question

An acrobat can safely land on the ground at speeds up to 15 m/s. what is the greatest height from which the acrobat can fall?

I know you need to use too formulas but mi lost as to what I can do with speed to find the distance..

the given formulas are v = gt     df = gt^2/2 t = sqr 2df/g

anonymous · Answer

use v=gt to find the time 
use the time in d = gt^2/2  to find the distance