By solving a quadratic equation, we will see that the ball hits the ground after 2.6 seconds.
How long does it take for the ball to hit the ground?
Here we need to solve the equation:
h(t) = 0 = -16t² + 40t + 4
This represents that the ball hits the ground.
So we just need to solve that quadratic equation, using the general formula we get:
[tex]t = \frac{-40 \pm \sqrt{(40)^2 - 4*4*(-16)} }{2*-16} \\\\t = \frac{-40 \pm 43.1 }{-32}[/tex]
We only care for the positive solution, which is:
t = (-40 - 43.1)/-32 = 2.6s
So the ball hits the ground after 2.6 seconds.
If you want to learn more about quadratic equations:
https://brainly.com/question/1214333
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