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at a point on the ground 15 ft from the tree, the distance to the top of the tree is 1 ft more than 2 times the height of the tree. find the height of the tree.

User Slwr
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1 Answer

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Let's say the tree is of height h. The point 15 ft away, the base of the tree, and the height of the tree form a right triangle, where the length of the sides are h, 2h + 1, and 15 (see attached image).

Using the Pythagorean theorem,
h^2+ 15^2 = (2h +1)^2

Simplifying it down, we get
3h^2+4h-224=0

We can use the quadratic formula to solve this, where the solutions are
(-4 \pm √(4^2 - 4 * 3 * (-224)) )/(2*3) = (-4 \pm √(2704) )/(6) = (-4 \pm 52)/(6)

Therefore the answers are
- (56)/(6) or
(48)/(6) =8

The answer is 8 since the height of the tree must be positive.
at a point on the ground 15 ft from the tree, the distance to the top of the tree-example-1
User Jesferman
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