What is 0 + 1?

This is so hard, please explain thoroughly.

0 + 1 = 1 //This is because the 0 is a negative number practically not adding nothing to the one.

The answer is 1. This is because 0 has no value (meaning it doesn’t affect other numbers) so that means anything plus 0 is that number. For example 1+0=1 because 0 doesn’t do anything.

Regular polygon area = n*side^2 / (4 * tan (180/n))
where "n" is number of sides
The formula is dependent on the side^2 term,
So, if we have an octagon that has sides 4 times as large, that means the area will be sixteen times larger.
side^2 = 4^2 = 16
So we multiply 25 cm^2 by 16 and we get
400 square centimeters.

Source:
http://www.1728.org/polygon.htm