Question 724176
A ball is thrown upward from the top of a 240 foot building. The ball is 256 feet above ground level a fter 1 second, and it reaches ground level in 5 seconds.  the height above ground is a quadratic function of the time after the ball is thrown.  Write the equation of this function. 
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It's the common formula for projectiles on Earth.
h(t) = -16t^2 + vt + h, h in feet
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h(1) = -16 + v + 240 = 256
v = 32 ft/sec (the upward speed at launch)
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h(t) = -16t^2 + 32t + 240 is the equation
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h(5) = -400 + 160 + 240 = 0 confirms impact at t = 5 seconds