Angular relationship question.

[CandyApples]

Homework Statement

A model rocket is launched at 50m/s, 35 degrees above horizontal. What is the horizontal displacement when its velocity vector is at 25 degrees.

Homework Equations

Kinematic equations, the relationship between sin cos and tan.

The Attempt at a Solution

tan(25)= .4663. I interpret this as the y (sin) velocity being .4663 the x velocity. Vy = .4663Vx

Vy = 50sin(25)-9.8t
.4663Vx = 50sin(25)-9.8t
Vx = (50sin25-9.8t)/.4663
Vx also equals 50*cos25 therefore...
50cos25 = (50sin25-9.8t)/.4663
(.4663*50cos25-50sin25)/-9.8 = t
t = 3.54E^-5.

Something about this answer seems very very wrong, especially when plugged back into the x displacement equation.

 

[ideasrule]

Vx also equals 50*cos25 therefore...

Why 50? The rocket decelerated due to gravity.