### Theory:

Working rule to construct a parallelogram:

Let us discuss the working rule to construct a parallelogram when the measures of two adjacent sides and a diagonal of a parallelogram are given.
Example:
Construct a parallelogram $$DUCK$$ with $$DU$$ $$=$$ $$8$$ $$cm$$, $$UC$$ $$=$$ $$6.5$$ $$cm$$ and $$DC$$ $$=$$ $$11$$ $$cm$$.

Construction:

Step 1: Draw a line segment $$DU$$ $$=$$ $$8$$ $$cm$$.

Step 2: With $$D$$ and $$U$$ as centres, draw two arcs of radii $$11$$ $$cm$$ and $$6.5$$ $$cm$$ respectively such that they intersect each other at $$C$$.

Step 3: Join $$DC$$ and $$UC$$.

Step 4: With $$C$$ and $$D$$ as centres, draw two arcs of radii $$8$$ $$cm$$ and $$6.5$$ $$cm$$ respectively such that they intersect each other at $$K$$.

Step 5: Join $$DK$$ and $$CK$$.

Step 6: $$DUCK$$ is the required parallelogram. The measure of $$KE$$ gives the height of the parallelogram $$DUCK$$.