Do Equal Angles at the Circumference Subtend Equal Chords?

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Do Equal Angles at the Circumference Subtend Equal Chords?

This may seem like a pretty basic question but I can't seem to find a definite answer on the internet and none of my textbooks mention this rule. Is this rule correct?

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It is true that equal angles at circumference subtend equal chords.

However, the explanation should NOT be taken as the chord length is proportional to the angle subtended at circumference.

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In the figure, all green marked angles are equal. Then $\dfrac {L}{2} = r \sin \theta$. After simplification (by treating r as constant), we have $\quad L \quad \alpha \quad \sin \theta \quad$ .