ABCD is a quadrilateral in which AB = BC and AD = CD. Show that BD bisects both the angles ABC and ADC.
Given: ABCD is a quadrilateral in which AB = BC and AD = CD
To prove :- ADB =
BDC
and ABD =
DBC
Proof: In ABD and
CBD
AB = CD (Given)
BD = BD (common)
AB = BC (given)
ABD
CBD (SSS congruency)
ABD =
CBD (by CPCT)
And ADB =
BDC (by CPCT)
Therefore, BD bisects both the angle ABC and ADC.
Hence proved