Editing Right angle (section)

== Rule of 3-4-5 ==
Throughout history, carpenters and masons have known a quick way to confirm if an angle is a true right angle. It is based on the [[Pythagorean triple]] {{nowrap|(3, 4, 5)}} and the rule of 3-4-5. From the angle in question, running a straight line along one side exactly three units in length, and along the second side exactly four units in length, will create a [[hypotenuse]] (the longer line opposite the right angle that connects the two measured endpoints) of exactly five units in length.