Answer: HL Theorem
Explanation:
In the given picture, there are two right triangles .
Here one side of both triangles are equal.
Also they both have one side as common.
So they are congruent by HL Theorem.
- HL theorem or hypotenuse leg theorem tells that if the hypotenuse and one leg of a right triangle are equal to the hypotenuse and one leg of another right triangle, then the triangles are congruent.