Angle of a Circle

A,B, C, and D lie on a circle, centre O.

SCT is a tangent and is parallel to OB.

What are the values of x, y, z and the reflex angle AOC.

• x=40, y=20, z=120, reflex angle AOC=130

• x=40, y=25, z=115, reflex angle AOC=230

• x=40, y=25, z=115, reflex angle AOC=130

• x=40, y=25, z=130, reflex angle AOC=230

The diagram shows a circle, centre O.
Points A, B, C and D lie on the circumference.
AB=BC
What is the value of angle ADC

• 76

• 52

• 104

• 38

Find ∠PRQ.

• 39°

• 90°

• 51°

• 15°

Find ∠DAR.

• 34⁰

• 17⁰

• 68⁰

• 136⁰

A ____ angle is an angle whose vertex is a the center of a circle.

• supplementary

• complimentary

• central

• obtuse

Which is true of a minor arc?

• It forms half a circle.

• It forms a whole circle.

• It measures greater than 180 degrees. 

• It measures less than 180 degrees.

Which of the following would be a major arc in the diagram?

• BC

• BCD

• CD

• AB

Which is true of a major arc?

• Forms half a circle.

• Forms a whole circle.

• Measures greater than 180 degrees.

• Measures less than 180 degrees.

What is the value of x?

• x = 160

• x = 40

• x = 80

• x = 360