SOLUTION: The height of a kite above the ground is four feet less than twice the distance from the person flying the kite to a point directly below the kite. The length of the string to the

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Question 548849: The height of a kite above the ground is four feet less than twice the distance from the person flying the kite to a point directly below the kite. The length of the string to the kite is 68 feet. How high is the kite?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Let x be the horizontal distance between the person flying the kite (or more precisely the hand holding the kite string), and the point directly below the kite.
Then, the height of the kite above the ground is2x-4
We have to assume that the hand holding the string is at the same level as the ground directly below the kite. Then it would look like this:
and we would apply Pythagoras theorem to state that x%5E2%2B%282x-4%29%5E2=68%5E2
We simplify the equation to get
x%5E2%2B4x%5E2-16x%2B16=4624 --> 5x%5E2-16x-4608=0
The quadratic formula gives us

We discard the negative solution, because distances are always positive numbers.
So x=%2816%2B304%29%2F10=320%2F10=32
And rhe height of the kite is
2x-4=2%2A32-4=64-4=60