a ball is dropped from the top of a building that is known to be 256 feet high.the formula for finding the height of the ball at any time t is h=256-16t^2,where t is measured in seconds.how many seconds will it take for the ball to hit the ground?

1 answer

it hits the ground when the height is zero. So, just solve

256-16t^2 = 0
(16-4t)(16+4t) = 0
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