a tree is standing upright.i want to cut it down at the base.how would i find out how tall it is. so that i could fall it without hitting any buildings.ie if it is 80 feet tall it should fall 80 feet?

Wait for a sunny day, not too near noon.

Stand next to it.
Measure your shadow, and the tree's shadow.

The tree's height will be in the same ratio as to your shadow.

Shalonda notices that when she stands next to the flagpole, she casts a shadow that is 8 feet long and that the flagpole casts a shadow that is 28 feet long. Little Shalonda is 4 feet tall. How tall, to the nearest foot, is the flagpole?

To find out the height of a tree, you can use a method called "tree height estimation." Here's a step-by-step approach to measure the height of the tree and determine how far it should fall:

1. Equipment needed: You will need a measuring tape, a long stick (such as a meter stick or yardstick), and a level area near the tree.

2. Measure a reference distance: Find a location where you can stand at a known distance away from the tree, but still have a clear line of sight to the top of it. Measure this distance accurately using the measuring tape.

3. Establish the angle to the top: Hold the long stick vertically so that it is perpendicular to the ground and the top of the stick aligns with the top of the tree. Make sure you are standing at the predetermined reference distance.

4. Measure the shadow: Observe where the shadow of the tree top falls on the stick. Measure the distance from the base of the stick to the point the shadow ends. This distance represents the height of the stick's shadow.

5. Measure the stick: Measure the actual length of the stick from its base to the point where you aligned it with the tree's top.

6. Calculate the tree height: Using some simple trigonometry, you can calculate the tree's height. Take the length of the stick and multiply it by the distance from the stick's base to the point where its shadow ends. Then divide that result by the distance from the measuring point to the tree. The formula is: (stick height × shadow distance) ÷ distance to the tree.

7. Determine the falling distance: Once you have measured the tree's height, you can plan the safe falling distance. It is generally recommended to have a clearing or a safe distance beyond the height of the tree to ensure it does not hit any buildings or obstacles.

Remember, accuracy may vary based on the angle of observation and your measuring technique. It is also important to take safety precautions when dealing with trees. If in doubt, you can consult a professional arborist for assistance.