Answer:
They are congruent by SAS:
Side: AB = CB
Angle: ∠ABD = ∠CBD
Side: BD = BD
Step-by-step explanation:
Two triangles are congruent if they have the same interior angles and the same length of their corresponding sides.
If two of the angles are equal, we can say that all the interior angles are equal.
So, based on the given information we get:
1. AC ⊥ BD means that AC is perpendicular to BD, therefore,
∠ADB = ∠CDB = 90°
2. It is given that ∠A = ∠C
3. Since both of their interior angles are equal, we can say that all the interior angles are equal and:
∠ABD = ∠CBD
4. The triangle ABC is isosceles because two of their interior angles are equal, therefore AB = CB
5. BD = BD because it is the same segment.
6. By SAS (Side-angle-Side) we can say that ΔABD = ΔCBD
Because the side AB is equal to side CB, the angle ABD is equal to angle CBD, and the side BD is equal to itself.