Question

congruence of triangle

Answer 1

In ∆DEB and ∆DFB
angle DEB=angle DFB (each 90°)
DE=DF (given)
DB=DB (common)
∆DEB is congruent to ∆DFB by RHS congruency criteria
hope it helps....

Answer 2

BFD = BED (90degree)

DB = DB (common)

DF = DE (given)

triangle DEB and DFB are congruent