In the following figure, AB =EF, BC = DE and ∠ B = ∠ E = 900.
Prove that AD =FC.
In Δ ABD and Δ FEC
AB=FE ( given )
∠FEC=∠ABD(900
BC = DE
in which CD is common part coming in both triangles
BC + CD = CD + DE
→BD=CE
∴ΔABDis≅ΔFEC by SAS rule of congruence
so AD=FC