Solving the polynominal: $s(t) = -16t^2 + 48t + 160$

Question

The height of a ball is thrown directly upward from an initial height of $160$ ft with an initial velocity of $48$ ft per second is given by the function:

$s(t) = -16t^2 + 48t + 160$, where $s(t)$ gives the ball's height above ground in feet, $t$ seconds after it is thrown. How long will it take for the ball to hit the ground?

Answer 1

HINT

You have a quadratic so, if you factor it and you will find the roots or in other words, when the balls hits the ground.

HINT $2$

You can factorize your polynomial by dividing by $-16$ and finding two numbers which add to $-3$ and multiply to $-10$

HINT $3$

Your answer should be in the form $-16(x-a)(x+b)$ where $a$ and $b$ are the numbers which make your equation zero or in other words, the roots.