Physics
posted by Maria .
A jetliner, traveling northward, is landing with a speed of 60 m/s. Once the jet touches down, it has 795 m of runway in which to reduce its speed to 5.6 m/s. Compute the average acceleration (magnitude and direction) of the plane during landing (take the positive direction to be northward).

Vi = 60
5.6 = 60 + a t
a t =  54.4
so
t = 54.4/a
795 = 60 t + (1/2) a t^2
795 = 60 (54.4/a) + .5 (2960/a)
795 a = 3264 + 1480
a = 2.24 m/s^2