In a right triangle, which of the following functions can be used to find the length of a side?

In a right triangle, the Pythagorean theorem is the most appropriate function to determine the length of a side. This theorem states that in a right triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the lengths of the other two sides. Mathematically, this is expressed as (a^2 + b^2 = c^2), where (c) is the hypotenuse and (a) and (b) are the other two sides.

By using the Pythagorean theorem, you can find the length of any side of the triangle as long as you know the lengths of the other two sides. This is particularly useful in various geometric problems involving right triangles, allowing for direct calculations of side lengths.

Other mathematical operations like addition, multiplication, and subtraction do not directly apply to this scenario when looking to find the lengths of sides in a right triangle in the context of its defining properties. These operations may be useful for other types of problems, but they do not serve to provide a formulaic relationship for solving side lengths in the specific case of right triangles.