CBSE Class 9 Answered

you can write the name of the first triangle in any way you want but the other triangle name should written to match it correctly according to the congruency.

in this particular question,

angle B = angle D..opp angles of a parallelogram are equal.

AD=BC

and

AB=CD...opp sides of a parallelogram are equal.

 so,

triangle ADC is congruent to triangle CBA.

this can be written in diff ways also.

 e.g.

triangle ACD cong to triangle CAB

or

triangle ADC  cong to triangle CBA