



 
Hi Leria. The equation you wrote for the earth should be h = 16t^{2} + vt + s and the equation for the moon should be h = 2.67t^{2} + vt + s. "s" is the starting height. "v" is the initial velocity (positive v means upwards). "h" is the height of the projectile (ball). The ball starts from 96 feet and lands at 0 feet (you are throwing the balls off of a cliff, perhaps). You are throwing the ball straight up. Thus your two equations become: These are two different times, so really two different "t" variables. So let e be the time it takes on the earth and m be the time it takes on the moon. The question asks how much longer the ball stays in motion (I presume it is a glass ball that breaks when it hits the surface, so there is no bouncing!) on the moon than on the earth. That's m  e. So you have and you want m  e. Use any method, such as factoring or the quadratic formula or completion of squares to determine each of e and m, then subtract to answer the question. Cheers,  


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