see here:
http://www.regentsprep.org/regents/math/geometry/gp15/circleangles.htm
Please mark this post as "answer" if it helped you and solved your problem
see here:
http://www.regentsprep.org/regents/math/geometry/gp15/circleangles.htm
Please mark this post as "answer" if it helped you and solved your problem