How Do You Calculate the Initial Velocity of a Projectile?

[jennypear]

projectile is fired w/an angle of 28.0degrees above the horizontal and from height 46.0m agove the ground. the projectile strikes ground w/a speed of 1.95xVo. Find Vo

I started using the eqution
(Vfy)^2=(Voy)^2+2*Ay*(delta Y)

Voy=Vosin(theta)=.47Vo
Vfy=1.954*Vosin(theta)=.92Vo

(.92Vo)^2=(.47Vo)^2+(2*-9.8*-46)
Vo=37.9

but my answer is wrong and I can't think of another way to answer the problem...Any ideas?

Thanks for your time!

 

[cookiemonster]

Let's try to keep it in one thread, please.

https://www.physicsforums.com/showthread.php?t=19333

cookiemonster