Answer:
1.62 seconds
Step-by-step explanation:
h = -16t² + 24t + 16.4
The initial height is 16.4 feet. The snowboarder lands 3.2 feet below this, or at a height of 13.2 feet.
13.2 = -16t² + 24t + 16.4
16t² − 24t − 3.2 = 0
Solve with quadratic formula:
t = [ -(-24) ± √((-24)² − 4(16)(-3.2)) ] / 2(16)
t = [ 24 ± √(576 + 204.8) ] / 32
t = 1.62
The snowboarder is in the air for 1.62 seconds.
