Therefore, by using converse of Basic proportionality theorem, we have
PQ || AC ...(i)
In ∆ADC, we have
Therefore, by using converse of Basic proportionality theorem, we have
SR || AC ...(ii)
Comparing (i) and (ii), we get
SR || PQ
Similarly, we can prove
SP || RQ
Hence, PQRS is a parallelogram.