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

A projectile is fired with an initial speed of 30 m/s at an angle of 60 degrees above the horizontal. The object hits the ground 7.5 s later.

knowns: x0=y0=t0= 0, v0=30 m/s, t2= 7.5 s, angle= 60 degree, ay= -9.8 m/s, v1y=0, and v1x=v0x=v2x.....find: y2-y0 y1-y0 and v2 angle

2. Relevant equations

1# vy2= y0 + v0y(t2-t0)+ 1/2ay(t2-t0)^2

2# v1y^2=v0y^2 + 2ay(y1-y0)

3. The attempt at a solution

I've found y2=-80.8 meters and am currently trying to figure out y1. I am using equation #2 and have this 0m/s^2= (30sin60m/s)^2 +2(-9.8m/s^2)(y1-0m) = y1= 34.4 m. I know the answer, but am having trouble isolating y1, i.e. not sure how to do the algebra. Everytime i attempt it, i get the wrong answer. any help will be appreciated, thanks.

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# Homework Help: Algebra question

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