Solving the quadratic equation, it is found that it took 2.5 seconds for the ball to hit the ground.
It is given by:
h(t) = -8t² + 18t + 5.
It hits the ground when h(t) = 0, hence:
-8t² + 18t + 5 = 0.
Which has coefficients a = -8, b = 18, c = 5, then:
[tex]\Delta = 18^2 - 4(-8)(5) = 484[/tex]
[tex]x_1 = \frac{-18 + \sqrt{484}}{2(-8)} = -0.25[/tex]
[tex]x_2 = \frac{-18 - \sqrt{484}}{2(-8)} = 2.5[/tex]
It took 2.5 seconds for the ball to hit the ground.
More can be learned about quadratic equations at https://brainly.com/question/24737967
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