Circle Theorem: Angles in the Same Segment Are Equal

Circle Theorem: Angles in the Same Segment Are Equal

All triangles drawn from a chord in a circle make the same angle at the circumference.

How to Use the Circle Theorem that the Angles in the Same Segment Are Equal

Question

What is the angle θ in the circle below?

Step-by-Step:

1

The angles subtended by the chord at the circumference of the circle are equal.

θ = 40°

Answer:

The angle θ is 40°.

Slider

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See Also

What is a triangle? What is an angle? What is a circle? What are the circle theorems?