The reasons are
- ΔCDA ≅ ΔBDA by SSS
- ΔCED ≅ ΔBED by SAS
How to get the reasons
ABCD is a kite, with its diagonals AD and BC.
Given:
AC = AB
CD = BD (Property of Kite)
In triangles ACD and ABD:
AC = AB
CD = BD (Property of Kite)
AD = AD (Common side)
Using the SSS (Side Side Side) Criteria:
ΔACD ≅ ΔABD
Therefore, ∠CDA = ∠BDA (CPCT - Corresponding Parts of Congruent Triangles)
Now, in triangles CDE and BDA:
CD = BD
∠CDE = ∠BDE
DE = DE (Common side)
By the SAS (Side Angle Side) Criteria:
ΔCDE ≅ ΔBDA
Hence, CE = BE (CPCT - Corresponding Parts of Congruent Triangles)
This demonstrates that AD bisects BC into equal parts.