Add angles I guess but math
Answer:
In mathematics, the magnitude or size of a mathematical object is a property which determines whether the object is larger or smaller than other objects of the same kind. More formally, an object's magnitude is the displayed result of an ordering ( or ranking ) - of the class of objects to which it belongs.
X2=4(5-1)
x2=4(4)
x2=16
x=4
Check: 4 squared (4 times 4) equals 16. When you square a number, you multiply the number by itself.
Use the Sum of Angles In a Triangle therom.