IM2.7 T7: Inscribed Triangles, Circumscribed Angles
2 things about tangents
All of the triangles above represent three circumscribed angles, formed by two tangents to a circle. A. Think about the way you constructed your circles, and try to come up with a way to calculate the size of angle ABC above if I tell you that arc AC is 120°. Describe your method in words. B. What do you know about segments AB and BC?