You drop a ball off a cliff at 500ft. how long does it take the ball to hit the ground? h(t)= -16t^2+500

The height when the ball drops would be 0, so plug in 0 for h(t):
0 = -16t^2 + 500 
Then you would solve for t, which in this case would equal to the time it takes to land.
-500 = -16t^2
t = 5.59, so it would take about 5.6 seconds to reach the ground.

H(t)=-16t^2+500
0=-16t^2+500
16t^2=500
t^2=500/16
t=±5.59 seconds
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