areaofquadrilateralABCD=areaofΔABC+areaofΔADCareaofΔABC=12×[x1(y2−y3)+x2(y3−y2)+x3(y1−y2)]A(x1,y1)=A(−2,−2)B(x2,y2)=B(5,1)C(x3,y3)=C(2,1)D(x4,y4)=D(−1,5)areaofΔABV=12[−2(1−1)+5(1−2)+2(−2−1)]⇒=12[0+15−6]⇒4.5unit2similarlyareaofΔADC⇒12[−2(1−5)+2(5+2)+(−1)(−2−1)]⇒12[8+14+3]=252=12.5unit2areaofquadrialtefral⇒4.5+12.5⇒17unit2