Since it is a quadratic equation: ax^2 + bx + c, we can use a formula for finding the time at which the rocket will reach its max.
[tex]\begin{gathered} Vx=\frac{-b}{2a} \\ Vx=\frac{-218}{2(-16)} \\ Vx=\frac{-218}{-32}(\text{Multiplying)} \\ Vx=6.8125\text{ } \\ \text{The answer would be 6.81 seconds (Rounding to the nearest hundredth of a second)} \end{gathered}[/tex]
