Askateboarder leaves a 12-foot tall ramp with an initial vertical velocity of 8 feet per second. the function f(h) = -8t^2 + 8t + 12 represents the height, h, in feet of the skateboarder after t seconds. how many seconds was the skateboarder airborne?

To answer this, we substitute 12 ft to the f(h) in the given equation,
                           f(h) = -8t² + 8t + 12 = 12
Subtracting 12 from both sides of the equation will give us an answer of,
                                     -8t² + 8t = 0
Then, we transpose 8 to the other side and divide the equation by -8 and t, we get an answer of t = 1 second. 

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