Thread: Sector angles

I have a triangle (not right angled) in a circle.

I know all the sides but none of the angles.

Is there a formula to find an angle? I need to know the one at the centre of the circle.

Thanks.

Originally Posted by GAdams

I have a triangle (not right angled) in a circle.

I know all the sides but none of the angles.

Is there a formula to find an angle? I need to know the one at the centre of the circle.

Thanks.

Is this an actual triangle or a wedge (sector) of the circle?

-Dan

Originally Posted by topsquark

Is this an actual triangle or a wedge (sector) of the circle?

-Dan

Its a triangle in a circle. O is the centre, A and B are points on the circumference. AB is a chord. Sides OA = 3cm = OB. And AB is 4cm.

Originally Posted by GAdams

Its a triangle in a circle. O is the centre, A and B are points on the circumference. AB is a chord. Sides OA = 3cm = OB. And AB is 4cm.

The use the Law of Cosines or the Law of Sines to find your angles.

-Dan