The Greek mathematician, mystic and scientist Pythagoras is best known for the Pythagorean theorem, which concerns what?

Question

Which Greek mathematician, from the 1st century BC, is best known for the theorem which bears his name and for leading a group who discovered square numbers and proposed that the earth was round, planets have an axis, and they travel around the sun?

Answer 1

Pythagorean theorem says - In a right-angled triangle , the square of the hypotenuse is equal to the sum of the squares of the perpendicular and the base.

Or lets understand if hypotenuse of a right angle triangle is c and perpendicular & base is a and b respectively then as per Pythagorean theorem -
a^2 + b^2 = c^2

or