Calculating Marble's Initial Height Using Projectile Motion Equations

[IAmSparticus]

Homework Statement

A marble is thrown horizontally with a speed of 10 m/s from the top of a building. When it strikes the ground, the marble has a velocity that makes an angle 68° with the horizontal. From what height above the ground was the marble thrown?

Homework Equations

delta y = (V02 sin2 theta)/(2g)

The Attempt at a Solution

4.39 m and 421.24. Neither correct.

 

[tiny-tim]

Hi IAmSparticus!

Show us your full calculations, and then we can see what went wrong, and we'll know how to help!