Given a building standing 400 feet tall, a tree 190 feet from the building, and another point 10 feet from the tree. find the height of the tree.

For this case we can model the problem as two similar rectangle triangles.
 We then have to simulate triangles:
 
 Rewriting we have:
 
 From here, we clear the value of x:
 
 
 the tree is 20 feet tall

You're doing something i dont know how to do but search up on google slope calculator maybe that will get you there