(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A gun has a muzzle speed of 80 meters per second.

What angle of elevation should be used to hit an object 150 meters

away? Neglect air resistance and use g = 9.8m/sec2 as the

acceleration of gravity.

2. Relevant equations

x = (vcos//theta)t

y = (vsin//theta)t - 1/2gt^2

g = 9.8 m/sec^2

3. The attempt at a solution

i substituted the given values:

x should be 150 and y should be 0 right?

150 = (80 cos\\theta)t

0 = ( 80sin\\theta)t - 4.9t^2

i can't figure out how to eliminate a variable or how to begin to solve for //theta

i solved for t using the "x" equation ( t = 15/8cos\\theta) and put that into the "y" equation

and i got this...

0 = 150tan//theta - 73.5/64(sec\\theta)^2

where do i go from here to find \\theta?

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