I learned that you need to know sin, cos, tans to find which are ratio`s in order to find the angle of the triangle.

I learned that adjacent is where ever the degree is and that the opposite side is the opposite of adjacent also you can find hypotenuse by looking at where the 90 degree angle is pointing at.

if you know I side of the triangle and one angle you can find the other sides and angles.

With trigonometry you can measure the tree by only seeing the angle of the tree with a device and finding the length and height of the tree.

*Tip*

Go closer and closer to tree until you hit 45 degree because then you can measure the distance and what ever the distance is it will be the same for the height.