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## Homework Statement

A projectile was launched from the top of a 100m tower upward at an angle theta to the horizontal with an initial velocity of 36m/s. The time of flight of the projectile was 8 seconds.

Determine:

i) The angle of projection

ii) The maximum height reached by the projectile

## Homework Equations

S=ut+1/2at^2

## The Attempt at a Solution

I am used to solving these questions when i am not given time but given both the horizontal and vertical distances. At which I use the quadratic formula to solve for theta. However in this case I can not do that as when i split my horizontal and vertical components and apply the above equations I am left with these.

Horizontally

S=36cos(?)*8

Vertically

-100=36sin(?)*8+0.5*-9.81*64

I have tried rearranging the vertical formulas to solve for theta

-1/2*-9.81*64-100/8=36sin(?)

301.42 = 36*sin(?)

sin-1(36/301.42) = 6.85 degrees

I really don't think that the answer is correct. The lecture who set the question will not give any answers.