Pythagoras was known for creating the Pythagorean Theorem, which was named after him. The Pythagorean Theorem uses the equation
to find the sides of a right triangle.
Pythagoras = photo 2
Ptolemy believed that Earth was at the center of the universe, not the Sun.
Ptolemy = photo 1
Archimedes was known for discovering the law of hydrostatics, which says that a body put in fluid loses weight equal to the weight of the amount of fluid it displaces.
Archimedes = photo 4
Eratosthenes was famous for making the first measurement of the size of Earth.
Eratosthenes = photo 3