Solve the problem.
-A ball is thrown vertically upward from the top of a building 128 feet tall with an initial velocity of 112 feet per second. The distance s (in feet) of the ball from the ground after t seconds is s = 128 + 112t - 16t² . After how
Many seconds will the ball pass the top of the building on its way down?

Question

Quizplus · Accepted Answer

The ball will pass the top of the building on its way down when its height is equal to the height of the building, which is 128 feet. Setting s equal to 128 and solving for t gives us the equation 128 = 128 + 112t - 16t^2. Simplifying, we get 0 = 112t - 16t^2, which simplifies further to t(112 - 16t) = 0. Solving for t, we find t = 7 seconds as one of the solutions, which is the time it takes for the ball to reach its maximum height and start descending.

Solve the Problem. -A Ball Is Thrown Vertically Upward from the Top of the Top