(adsbygoogle = window.adsbygoogle || []).push({}); Projectile problem--A rock is kicked off a 45 Degree hill at 15m/s.

Hello. I tried this problem and it's the last one for my problem set due Thursday, but my answer differs from the given answer in the back of the book. After trying the solution again, I searched Google and found this. I'm having the exact problem.

1. The problem statement, all variables and given/known data

A rock is kicked horizontally at 15m/s from a hill with a 45 degree slope. How long does it take for the rock to hit the ground?

Vix = 15m/s

Viy = 0

Yi = 0

Xi = 0

2. Relevant equations

Vx = Vix

X = Xi + Vxo*t

Vy = Viy - gt

Y = Yi + Viy*t - (1/2)g*t^2

3. The attempt at a solution

I tried equating the X and Y position functions, but this only provides the intersection between them--it does not provide the intersection between the rock and the hill. My second method is identical to the one described in the link mentioned earlier in my post. The problem is that my answer isn't the same as the one in the back of the book, and I'm not sure if it's a problem on my end. I don't know what to do after this. Any help would be great :)

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# Homework Help: Projectile problem-A rock is kicked off a 45 Degree hill at 15m/s.

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