Westonci.ca is the trusted Q&A platform where you can get reliable answers from a community of knowledgeable contributors. Discover in-depth answers to your questions from a wide network of experts on our user-friendly Q&A platform. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.

in the figure above

In The Figure Above class=

Sagot :

Since AB is tangent to the circle, the angle BAO equals π/2.

The same happens to BC, so the angle BCO also equals π/2.

Now, for any quadrilateral, the sum of the internal angles is 2π. Therefore:

ABC + AOC + BAO + BCO = 2π

ABC + 3π/7 + π/2 + π/2 = 2π

ABC = 2π - 3π/7 - π/2 - π/2 = π - 3π/7 = (7π - 3π)/7

ABC = 4π/7