In Fig. 9.4, the area of parallelogram ABCD is :
(A) AB × BM
(B) BC × BN
(C) DC × DL
(D) AD × DL
Answer: [C]
Solution.
We know that
Area of parallelogram = Base × corresponding altitude
Area of parallelogram ABCD = AB × DL … (1)
Now, AB = DC (opposite sides of a parallelogram are equal)
Substituting in (1), we get
Area of parallelogram ABCD = DC × DL
Hence, option (C) is the correct answer.
We can check for other options as well.
In option (A), AB × BM; BM is not the corresponding altitude to the side AB
In option (B), BC × BN; BC is not the corresponding altitude to the side BN
In option (D), AD × DL; AD is not the corresponding altitude to the side DL
Therefore option (C) is correct.