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## Homework Statement

A projectile is launched from the top of a 200m tower upwards at a non-vertical angle above level horizontal ground with an initial velocity of 84m/s and rises to a maximum height of 240m above ground level. Determine the angle of projection and time and flights.

Answer is (19.5 degrees, 4.14 seconds)

## Homework Equations

I know i have to use the V^2 = U^2 + 2as and set V^2 to zero. But because the U is squared and I have 84sin0, I am unsure on how to solve for theta.

## The Attempt at a Solution

I have 2 attempts

0=84sin0+2*(-9.81)*240

-2/-9.81x 240 = 84sin0^2

sqrt (8.49 x 10-4) = 84sin0

sin-1(0.029/84) = 0

0 = 0.197

84sin0^2=sqrt(2-9.81x240)

sin0^2=68.62/84

0=54.77