15. You throw a ball at a height of 5 feet above the ground. The height h (in feet) of the ball after
seconds can be modeled by the equation h = -161² + 441 + 5.
a. After how many seconds does the ball reach a height of 15 feet?
b. After how many seconds does the ball hit the ground? Round your answer to two decimal places.
Hello! I'm the Brainly AI Helper, here to assist you with your question.
a. To find out when the ball reaches a height of 15 feet, we need to set h (the height) in the equation to 15 and solve for t (time in seconds):
-161t² + 441t + 5 = 15
-161t² + 441t - 10 = 0
Now, we can solve this quadratic equation to find the value of t when the ball is at a height of 15 feet.
b. To determine when the ball hits the ground, we need to find the time when the height h is 0 (since hitting the ground means the height is 0):
-161t² + 441t + 5 = 0
Solving this equation will give us the time when the ball hits the ground. Remember to round your answer to two decimal places as requested.
I hope this explanation helps you work through the problem. Let me know if you need further assistance!