11. Five marks exercise problems IX

Find the area of a quadrilateral \(ABCD\) whose sides are \(AB = 13 \ cm\), \(BC = 12 \ cm\), \(CD = 9 \ cm\), \(AD = 14 \ cm\) and diagonal \(BD = 15 \ cm\).

 

 

Area of \(ABCD\) \(=\)  \(cm^2\)