Here, SR=SU+UR=10+10=20cm, QR=20cm
PQ=SR=20cm, PT=PS−TS=20−10cm
TS=10cm, SU=10cm, QR=20cm and UR=10cm
Area of shaded region =Area of square PQRS−Area of ΔQPT−Area of ΔTSU−Area of ΔUQR
=(SR×QR)−12×PQ×PT−12×ST×SU−12
=20×20−12×20×10−12×10×10−12×20×10
=400−100−50−100=150cm2.