Final answer:
The Pythagorean Theorem allows us to calculate the diagonal of a rectangle by treating it as the hypotenuse of a right triangle with the rectangle's sides. The formula for the diagonal is the square root of the sum of the squares of the sides (d = √(A² + B²)).
Step-by-step explanation:
The Pythagorean Theorem is a fundamental principle in geometry that relates the lengths of the sides of a right triangle. According to the theorem, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. If we label these sides as a and b, and the hypotenuse as c, the theorem can be written as a² + b² = c². Solving for the hypotenuse, we get c = √(a² + b²).
When considering the diagonal of a rectangle, the diagonal forms the hypotenuse of a right triangle with the sides of the rectangle. Therefore, if a rectangle has sides of lengths A and B, the length of the diagonal d can be found using the Pythagorean Theorem as follows: d = √(A² + B²), which corresponds to option A.