Question

In parallelogram ABCD (fig3) , show that ABD = CDB ​

Answer 1

Answer:

those 2 triangles are congruent

so by cpct we can say the angles are also equal

Answer 2

ABCD is a parallelogram So

AB = DC ( opposite sides of parallelogram are equal) ABD

AD = BC ( opposite sides of parallelogra are equal)

Angle DAB = DCB( opposite angles of parallelogram are equal)

angle CDB = angle ABC ( opposite angles of parallelogram are equal)

now your solution

in angle ABD and angle CDB

AB = CD ( given)

AD = BC ( given)

angle ABD = angle CDB ( alternate interior angles)

so angle ABD congruence to CDB

by cpct angle ABD = CDB...

hope it's help ✌✌