Question

A projectile is launched from ground level to the top of a cliff which is 195 m away and 155 m high. If the projectile lands on top of the cliff 9.2 s after it is fired, find the initial velocity of the projectile (magnitude and direction). Neglect air resistance. Also calculate the angle

Answer 1

Well, you have some algebra ahead.

Vertical:
155=VsinTheta*t-4.9t^2
Horizontal:
195=VcosTheta*t

you are given t.

So you have two equations, two unknowns.
Here is what I suggest. Put both equations in the form of

V*trigfunction=some number

then square both sides.
add the equations, you should get something like this:
V^2(cosTheta ^2 + sinTheta ^2)=number^2

well, you know the ( ) is 1, which allows you to solve for V. Then substitute back to solve for theta.

Have fun.