Question

Given AD CB ADB CBD Prove: ∆ADB ≅ ∆CBD

Look at the proof. Name the postulate you would use to prove the two triangles are congruent.

Answer 1

We will use the SAS (SIDE-ANGLE-SIDE) to prove that two triangles are congruent.

Answer 2

SAS postulate.

Explanation:

Notice that sides AD and BC are congruent, also DB is a common side to both triangles. At this point, we already have two corresponding congruent sides.

Additonally, angles ADB and CBD are congruent. In summary, we have two pair of corresponding sides congruent, and one pair of corresponding angles congruent (which is formed by the congruent sides).

Based on all the given information, by SAS postulate triangles ADB and CBD are congruent.