Question

Please help quickly!

What is the measure of Arc CB. How did you determine this?

Answer 1

As shown in picture,

Angle CDF = Angle BDE = 54 deg (pair of opposite angles)

Angle CDB = 180 - CDF = 180 - 54 = 126 deg (BF is a diameter).

=> Arc CB = Angle CDB = 126 deg (property of angle on circle)

Hope this helps!

:)