Question

Darcy kicks a ball that is represented by the function h\left( t \right) = - 16{t^2} + 50t h ( t ) = − 16 t 2 + 50 t where t stands for time and h(t) stands for the height of the ball in feet. How long will it take for the ball to hit the ground?

Answer 1

Check the picture below.

$\bf h(t)=-16t^2+50t\implies 0=-16t^2+50t\implies 0=-t(16t-50) \\\\\\ \begin{cases} 0=-t\implies &0=t\\ ------\\ 0=16t-50\\ 50=16t\\ \frac{50}{16}=t\implies &\frac{25}{8}=t \end{cases}$

it hits it twice, once at the beginning, 0 seconds, and when it hits the ground at the end.