Question

A pet owner throws a tennis ball for his dog to chase. The tennis ball's height in feet after it is thrown upward is given by -160t^2 + 32t + 4, where t represents the time in seconds after the ball was thrown. After how many seconds will the ball hit the ground? Round your answer to the nearest hundredth if necessary.

a) 0.19 seconds
b) 0.41 seconds
c) 0.81 seconds
d) 2.00 seconds

Answer 1

The ball will hit the ground after approximately 0.19 seconds (choice a).

Step-by-step explanation:

The equation for the height of the tennis ball is given by -160t^2 + 32t + 4, where t is the time in seconds after the ball was thrown. To find when the ball will hit the ground, we need to set the height equal to zero and solve for t. Using the quadratic formula, we get t = 0.19 seconds and t = 2.0 seconds. Since we are only interested in the time it takes for the ball to hit the ground, we round our answer to the nearest hundredth, which is 0.19 seconds (choice a).