help me pleaseee

Question

A ball is thrown into the air from a height of 4 feet at time t = 0. The function that models this situation is h(t) = -16t^2 + 64t + 4, where t is measured in seconds and h is the height in feet. Use this information to answer the following questions .

after how many seconds will the ball hit the ground?

Answer 1

If we are looking for where the ball will hit the ground, we need to plug in 0 for our height. This would look like:

0 = -16t^2 + 64t + 4

Now, this is a quadratic equation so we can factor it out. You can either factor it normally or use the quadratic formula. Another good way to do is to use your calculator and graph it and look for the zeroes. I'll let you try that bit, but your answer for that should be that you find zeroes at about t = -0.06 and t = 4.06

It isn't possible for us to have negative time, so the only option for when the ball will be at 0 height, also known as on the ground, will be at about 4.06 s

Let me know if you need clarification or have any questions!