How do you do a Pythagorean theorem?

How do you do a Pythagorean theorem?
The Pythagorean theorem can be done this way.
a+b=c
lets say that you have a triangle with three sides, but you are only given two. Their values are 3 and 4. Now you have to fill in the values with a=3 and b=4 (doesn't matter which order you put it in)
3+4=c
c is still unknown so we have to do the next step.
3 is 9 and 4 is 16. knowing this, we have to do this next:
9+16=c
9+16 is 25.
25=c
now you must get rid of the . you do this by using the square root.
don't ask me why you square root, that's just how the Pythagorean theorem works.
25=c
the square root gets rid of the c squared so its just the square root of 25.
5=c
triangle sides: 3,4,5
The process can also be reversed.
a=c-b
or
b=c-a

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