The side of quardrants are- AB=13 cm,BC=16 cm, CD=20 cm,DA=5 cm,if BD=12 cm, find area of quardants using heron formula.?

Consider ΔABD :
s = (13 + 5 + 12)/2 cm
s = 15 cm

By heron formula, Area of ΔABC
= √[15 × (15 - 13) × (15 - 5) × (15 - 12)] cm²
= 30 cm²

Consider ΔBCD :
s = (16 + 20 + 12)/2 cm
s = 24 cm

By heron formula, Area of ΔBCD
= √[24 × (24 - 16) × (24 - 20) × (24 - 12)] cm²
= 96 cm²

Area of quadrilateral ABCD
= Area of ΔABC + Area of ΔBCD
= (30 + 96) cm²
= 126 cm²