This is really confusing me?

Question

A particle travels between two parallel vertical walls separated by 11 m. It moves to ward the opposing wall at a constant rate of 6.3m/s. It hits the opposite wall at the same height and the acceleration of gravity is 9.8m/s^2. I need to find what its speed will be when it hits the opposing wall. I thought it was 6.3m/s but it's not.

The particle travels in the shape of a upside down parabola.

Answer 1

vx=6.3 and t=11/6.3 find vy from equation v=v0-gt knowing that at time t v=-v0 so in y direction is vo=gt/2
then speed = (vx^2+vy^2)^.5