90 degrees 5 squared + 12 squared = 13 squared which demonstrates, according to the Pythagoras theorem, that the angle between the two shorter sides is a right angle.
In mathematics, what is the name for the following sequence of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765 ...
"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?
