## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$$t=3$$
We are given the following equation: $$h=48t-16t^2$$ Thus, plugging in $0$ for $h$ and looking for the solution besides t=0, we find: $$0=48t-16t^2 \\ t_{1,\:2}=\frac{-48\pm \sqrt{48^2-4\left(-16\right)0}}{2\left(-16\right)} \\ t=3$$