Question

write formula of cyclic quadrilateral

Answer 1

the sum of opposite angles is 180.and every cyclic parallelogram is a rectangle

Answer 2

In a cyclic quadrilateral, the sum of each pair of opposite angles is 180 degrees. If a quadrilateral has one pair of opposite angles that add to 180, then you know it is cyclic

so Area. where s, the semiperimeter, is
s = 12(a + b + c + d). 

Hope this helps you dude ✌️✌️✌️