Answer:
A. Find h(10) = 0 . . . (it is not)
B. h(5.235) = 0; hang time was about 5.235 seconds
Step-by-step explanation:
The hang time of the ball is the value of x in h(x) such that h(x) = 0.
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<h3>A.</h3>
Juan can show the hang time is 10 seconds by finding h(10) = 0. The value of h(10) is ...
h(10) = -16(10²) +83(10) +4 = -1600 +834 = -766 ≠ 0
Juan cannot prove the hang time was 10 seconds.
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<h3>B.</h3>
The hang time is the solution to ...
h(x) = 0
-16x² +83x +4 = 0 . . . . . use the given expression for h(x)
x² -5.1875x = 0.25 . . . . divide by -16
x² -5.1875x +6.7275390625 = 6.9775390625 . . . . add (5.1875/2)²
(x -2.59375)² = 6.9775390625 . . . . . . . . . . rewrite as a square
x = 2.59375 ±√6.9775390625 ≈ {-0.048, 5.235} . . . . square root, find x
The hang time of the ball was about 5.235 seconds.
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