SOLUTION: Ethel tosses a softball upward. When the ball leaves her hand 5 feet above the ground it has an initial upaward velocity of 66 feet per second. How high can Ethel toss the ball?

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Question 139689: Ethel tosses a softball upward. When the ball leaves her hand 5 feet above the ground it has an initial upaward velocity of 66 feet per second. How high can Ethel toss the ball?

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Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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Ethel tosses a softball upward. When the ball leaves her hand 5 feet above the ground it has an initial upward velocity of 66 feet per second. How high can Ethel toss the ball?
:
Using the equation h = -16t^2 + 66t + 5; find the axis of symmetry (x=-b/(2a):
t = %28-66%29%2F%282%2A-16%29
t = %28-66%29%2F%28-32%29
t = 2.0625 sec, when the ball reaches max height
:
Substitute 2.0625 in the equation to find h:
h = -16(2.0625^2) + 66(2.0625) + 5;
:
h = -16(4.2539) + 136.125 + 5
:
h = -68.0625 + 141.125
:
h = 73 ft max height of the ball