Which of the following are examples of when HL Theorem should be used to prove congruency? (Check all that apply)

The HL (Hypotenuse-Leg) Theorem states that if the hypotenuse and a leg of one right triangle are congruent to the hypotenuse and corresponding leg of another right triangle, then the two triangles are congruent.

Therefore, the HL Theorem should be used to prove congruency in the following situations:
- When given that the hypotenuse and a leg of one right triangle are congruent to the hypotenuse and corresponding leg of another right triangle.
- When proving the congruency of right triangles that have congruent hypotenuses and corresponding legs.

In summary, the HL Theorem should be used when dealing with right triangles and there is congruency between the hypotenuse and corresponding leg of two triangles.