How do you find time given vi, acceleration, and displacement

[xcfzm94]

using

d=vit+ 1/2at^2

my subs are

75 =3t +1/2 (9.81)t^2 (if an object is dropped is gravity still -9.81?)

where do i go from here

 

[jtbell]

Have you studied how to solve quadratic equations?