"""The sum of the squares of the lengths of the four sides of a parallelogram equals the sum of the squares of the lengths of the two diagonals"" is known as what?"
Parallelogram identity Parallelogram equality Parallelogram equation Parallelogram law Parallelogram rule
parallelogram law parallelogram identity parallelogram equality parallelogram equation parallelogram rule
parallelogram law
WikipediaEntity
Parallelogram law