Which of the following describes the longest side of a right triangle?

In a right triangle, the longest side is known as the hypotenuse. This side is opposite the right angle and is always longer than either of the other two sides, which are referred to as the legs of the triangle. The hypotenuse can be determined through the Pythagorean theorem, which states that the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the legs.

This characteristic makes the hypotenuse a critical element in trigonometry and geometry, as it serves as a reference point for calculating angles and distances in various applications. The designation of the hypotenuse as the longest side is fundamentally tied to the definition and properties of right triangles, underscoring its importance in geometric studies.