If A B C D is a cyclic quadrilateral then what is A+ B - C - D equal to?

Step-by-step solution

A + B - C - D In cyclic quadrilateral, ABCD aligned & A + C =180^ , B + D =180^ & A =180^ - C , ~B =180^ - D & (180^ - C )+ (180^ - D )- C - D & C + D - C - D =0 aligned