Ok I am going to try and make this as easy as possible…
When you do ranges from your stand think of it as a triangle. You have 2 sides of the triangle 15 yards to the target, and 5 yards up the tree (I know it is actually 5.3 yards but for math purposes I am bringing you down a foot). Now all you need to do is find the other side of your triangle using the formula…
A squared + B squared = C squared
So then you plug in the numbers
5 squared + 15 squared = C squared
5x5 + 15x15 = C squared
25 + 225 = C squared
250 = C squared
Now to find out “C” (or the distance you are actually shooting) you would do the opposite of squaring which would be the SQUARE ROOT….
So take the Square Root of 250….
15.81 = C
So in the case you presented you would be shooting about 16 yards…
I would suggest investing in a Calculator
Happy Hunting!