As you probably know from your high school days, the Pythagorean theorem can be used to calculate the lengths of the sides of triangles.
Although the Babylonians never described the theorem, we know they used it, since we have found tables with Pythagorean triples, which are whole numbers which satisfy the equation a²+b²=c².
For instance in the top row of the depicted clay tablet we read 119 and 169, which are part of the following Pythagorean solution: 120²+119²=169². Every row contains another triple like this.
"The Great World History Book"