Look at the measures shown in the adjacent figure and find the area of

In the given fig. ∆ PRS is right angle triangle at S

Therefore, using Pythagoras theorem,

PS² + SR² = PR²

= 39m

Now,

Area of ∆PRS = × base × height

= ×PS×SR

= ×36×15

= 270 sq m

Now the area of triangle PQR, using heron’s formula

Here, sides are 56 cm, 25 cm, and 39 cm

Therefore,

S = 60

S - a = 60 - 56 = 4

S - b = 60 - 25 = 35

S - c = 60 - 39 = 21

= 420 sq m

Hence, the area of the quadrilateral PQRS = area of ∆PQR + ∆PSR

= 420 + 270

= 690 sq m