SOLUTION: An object is dropped from an airplane flying 784 feet above the ground. The height 'h' above the ground 't' seconds after it is dropped is given by the formula h=16t+784. How long

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Question 91225: An object is dropped from an airplane flying 784 feet above the ground. The height 'h' above the ground 't' seconds after it is dropped is given by the formula h=16t+784. How long will it take for the object to hit the ground?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
When the object hits the ground, the height, h, will be zero. So if you set the formula for h equal to zero and solve for the time, t, this will tell you how long it will take for the object to hit the ground.
h = 16t + 784 ...but I think you may have a typo here! It should be:
h+=+-16t%5E2+%2B+784 So, set this = 0 and solve for t.
0+=+-16t%5E2%2B784 Add 16t%5E2 to both sides.
16t%5E2+=+784 Divide both sides by 16.
t%5E2+=+49 Take the square root of both sides.
t+=+7 or t+=+-7 Discard the negative solution as the time, t, should be a positive value.
It will take the object 7 seconds to hit the ground.