letting the water be at height 0, just solve
40 + 20t - 4.9t^2 = 7
a rock is thrown upward with a velocity of 20 meters per second from the top of a 40 meter high cliff, and it misses the cliff on the way back down. when will the rock be 7 meters from the water, below? round your answer to two decimal places
2 answers
t=56