It is not known for sure where exactly Pythagorean Theorem was discovered. But Pythagoras a Greek Mathematicians has discovered this. So I would assume in Ancient Greece. I found this related website which explains and also has a calculator.
See below for the related link
They were shocked.
Tradition dictates that the Pythagorean Theorem was discovered by Pythagoras, a Greek mathematician, who lived around 570-495 BC.
my moms house
Chinese and babylonians
he was about 48-49 years of age jk
Oh yes, the Pythagorean Theorem has been proven.
The Pythagorean theorem uses the right triangle.
Pythagoras did not borrow the Pythagorean Theorem from any particular civilization. The theorem, which states that in a right-angled triangle the square of the hypotenuse is equal to the sum of the squares of the other two sides, was discovered by Pythagoras himself and is named after him.
There are 19 various aspects of Pythagoras theorem. Pythagorean Theorem (1) Pythagoras Theorem(2) Pythagorean Theorem (3) Pythagorean Theorem (4) Pythagoras Theorem(5) Pythagorean Theorem(6) Pythagrean Theorem(7) Pythagoras Theorem(8) Pythagorean Theorem (9) Hyppocrates' lunar Minimum Distance Shortest Distance Quadrangular Pyramid (1) Quadrangular Pyramid (2) Origami Two Poles Pythagoras Tree(1) Pythagoras Tree(2) Theorem by Pappus
You can use pythagorean theorem twice to find the diagonal of a cube
the standard form of the Pythagorean Theorem is :a2 + b2 = c2
The Pythagorean theorem is a2 + b2 = c2