Question

pairs of opposite angles of a cyclic quadrilateral are supplementary

Answer 1

yes they are supplementary i. e 180°

Answer 2

let us take angles as w,x, y, z


we all know that quadrilateral has 360 so w+x+y+z+w+x+y+z=360

2 (w+x+y+z)=360

w+x+y+z=180