Final answer:
The length of segment RT can be found using the Pythagorean theorem, which states that in a right triangle, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. Therefore, the correct answer is √20.
Step-by-step explanation:
The length of segment RT can be found using the Pythagorean theorem, which states that in a right triangle, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. In this case, we can see that segment RT is the hypotenuse of a right triangle with sides measuring 4 units and 2 units. So, the length of segment RT can be found as follows:
Length of segment RT = √(4^2 + 2^2) = √(16 + 4) = √20
Therefore, the correct answer is a) √20.