Answer:
A. Hypotenuse-leg (HL) congruence.
HL, when you have 2 right triangles and their hypotenuses are congruent you are able to say HL
Step-by-step explanation:
We know that the hypotenuse-leg theorem states that if the hypotenuse and one leg of a right triangle are congruent to hypotenuse and corresponding leg of another right triangle, then the triangles are congruent.
hypotenuse(AB) of △BDA equals to hypotenuse (CD) of △DBC.
BDA and DBC share a common side DB.
Using Pythagorean theorem we will get,
We have been given that CD=AB, Upon using this information we will get,
Upon subtracting from both sides of our equation we will get,