Question

1. which congruence postulate or theorem must you use before proving ∠a≅∠c? sas congruence postulate sss congruence postulate hl theorem ssa congruence postulate

Explanation:

Step1: Identify given information

We have two right - triangles $\triangle ABD$ and $\triangle CBD$, with $AD = CD$ (marked equal sides) and $BD$ is common to both triangles. Also, $\angle ABD=\angle CBD = 90^{\circ}$.

Step2: Recall congruence postulates

The Hypotenuse - Leg (HL) theorem states that if the hypotenuse and a leg of a right - triangle are congruent to the hypotenuse and a leg of another right - triangle, then the two right - triangles are congruent. Here, in right - triangles $\triangle ABD$ and $\triangle CBD$, $AD$ and $CD$ are legs and $BD$ is the common hypotenuse.

Answer:

HL theorem