Question

Which is the pair of congruent right angles?

Answer 1

The little squares at corner-B and corner-E were drawn there
to show that those are right angles.

Answer 2

Answer with explanation:

In Δ AB C and Δ A E D

1.≡∠AB C= ∠ A E D→→→[Each being 90°]

2.≡ B C= E D →→[Given]

3. ≡ ∠A CB = ∠ A DE →[Given]

⇒Δ AB C ≅ Δ A E D [By S AS]

≡∠ A B C and ∠ A E D, are congruent right angles.

In the Diagram given

∠AB C= ∠ A E D=90°