Identify all the central angles of circle O.

angle AOB, angle BOC, angle AOC
angle AOB, angle BOC, angle OBC, angle AOC
angle AOB, angle BOC, angle OBC
angle AOB, angle BOC

Is it D?

http://i68.tinypic.com/iy3evo_th.jpg

Question

Identify all the central angles of circle O.

    angle AOB, angle BOC, angle AOC
    angle AOB, angle BOC, angle OBC, angle AOC
    angle AOB, angle BOC, angle OBC
    angle AOB, angle BOC

Is it D?

http://i68.tinypic.com/iy3evo_th.jpg

anonymous · Answer

Please can someone check it?

anonymous · Answer

I will fan you!

anonymous · Answer

Please just someone check it?

anonymous · Answer

omg i have the same question XD

anonymous · Answer

Could you help me then? Thank you. ^_^

anonymous · Answer

Im not sure of it myself. I asked it farther down and im waiting for help but if i get any information thats useful I will let you know

mathstudent55 · Answer

A central angle of a circle has the center of the circle as the vertex and radii as sides.

anonymous · Answer

Thank you. I'm in desperate need to fix my math grade. No one around me is good at math, and I need someone who can explain it in a less complicated way. I think D is correct but I rather not take a chance.

anonymous · Answer

Hmmm....so AOC is crossed out.

anonymous · Answer

so that takes out 2 answers

mathstudent55 · Answer

Angles AOB abd BOC are definitely central angles.
Angle AOC is or is not depending on the definition of an angle you are using.
If your angle definition allows for a 180-deg angle, then angle AOC is also a central angle.

anonymous · Answer

Do I think the answer is D?

anonymous · Answer

*so

mathstudent55 · Answer

Sometimes Geometry limits angles to measures between 0 and 180 deg.
Other times it does not.
In my opinion, AOC is a central angle measuring 180 deg.

anonymous · Answer

Hmmm...but AOC is a semicircle?

anonymous · Answer

So, wait it could possibly be considered a central angle then?

mathstudent55 · Answer

I think the answer is A, to include central angle AOC also.

anonymous · Answer

I'm going with, A then. Thanks for all of the help!

mathstudent55 · Answer

AOC is a 180-deg angle.

anonymous · Answer

Thanks, you are a life saver. Also thanks for taking the time to explain it.

mathstudent55 · Answer

Wikipedia explains that the measure of a central angle is between 0 and 360 deg, so 180 deg is certainly acceptable. https://en.wikipedia.org/wiki/Central_angle

mathstudent55 · Answer

You're welcome.

anonymous · Answer

http://www.mathopenref.com/circlecentral.html I went here. Thanks again!

mathstudent55 · Answer

You're weclome.