Given below is a parallelogram ABCD.
Question:

Given below is a parallelogram ABCD. Complete each statement along with the definition or property used.

(ii) ∠DCB =

(iii) OC =

(iv) ∠DAB + ∠CDA =

Solution:

The correct figure is

(i) $\mathrm{AD}=\mathrm{BC}$ (opposite sides of a parallelogram are equal)

(ii) $\angle \mathrm{DCB}=\angle \mathrm{BAD}$ (opposite angles are equal)

(iii) $\mathrm{OC}=\mathrm{OA}$ (diagonals of a prallelogram bisect each other)

(iv) $\angle \mathrm{DAB}+\angle \mathrm{CDA}=180^{\circ}$ (the sum of two adjacent angles of a parallelogram is $180^{\circ}$ )