In given figure if AC = BC, ∠DCA = ∠ECB and ∠DBC = ∠EAC, then DC =
We have,
∠DCA = ∠ECB
⇒ ∠DCA + ∠ECD = ∠ECB + ∠ECD
⇒ ∠ECA = ∠DCB .......(i)
Now, in Δs DBC and EAC, we have
∠DCB = ∠ECA [From (i)]
BC = AC [Given]
and ∠DBC = ∠EAC [Given]
So, by ASA criterion of congruence
ΔDBC ≅ ΔEAS
⇒ DC = EC [ Correcponding parts of congruent triangles are equal ]