A projectile fired from ground level at 25 m/s hits the ground 31.25 m away. At what angle was it fired?(adsbygoogle = window.adsbygoogle || []).push({});

I wrote equations for t for both x and y

t = delta x / velocity x

t = 2 * viy/a

and set them equal to each other to eliminate t

and replaced velocityx with cos(theta)*25

and replaced velicityinitialy with sin(theta)*25

delta x / cos(theta)*25 = 2*sin(theta)*25/a

25 / cos(theta)*25 = 2*sin(theta)*25/9.81

sin(theta) * 25 * cos(theta)*25 = 153.28

My trig is not that good. How do I continue? Or is this even the right way to tackle this proble? Is there an easier way?

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# Homework Help: Trajectory of a projectile

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