Question

the height of a ball thrown directly up with a velocity of 40 feet per second from a initial height of 5 ft is given by the equation h(t)=-16t2+40t+5, where t is the time in seconds and h is the balls height, measured in feat. when will the ball hit the ground?

Answer 1

The equation is h=-16t²+40t+5.The ball will hit the ground when h=0. So:
0=-16t²+40t+5
16t²-40t-5=0
Using the quadratic formula, we get a positive value for t of 2.61930639376 seconds.
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