Question 369536
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Hi,
H = -16t^2 + 64t + 6
Find all times t that the object is at a height of 54 feet off the ground.
54 = -16t^2 + 64t + 6
16t^2 - 64t -6 + 54 = 0
16t^2 - 64t + 48 = 0
16[t^2 - 4t + 3] = 0
 t^2 - 4t + 3 = 0
factoring
(t-3)(t-1) = 0
(t-3)= 0  t = 3 sec
(t-1)= 0  t = 1 sec

{{{graph(500, 500,-70,70,-70,70,-16x^2 + 64x + 6) }}}