The given triangle is a right angled triangle and therefore, the Pythagorean Theorem will be applicable to it. As is clearly visible, [tex] z [/tex] is the hypotenuse and [tex] y [/tex] is the perpendicular side of the given right triangle.
Therefore, the third side of the triangle can be found out with the use of the Pythagorean Theorem as:
Third Side=[tex] \sqrt{z^2-y^2} [/tex]
Thus, Option D looks like the best option
