Opposite angles of cyclic quadrilateral are supplementary.
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Opposite angles of cyclic quadrilateral are supplementary.
Theorem related with circle
In English: https://youtu.be/KdDV1Adz_9U
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Please watch: "If ?^?.?^?=(?^? )^?, show that ?/?+?/?=??−?."
https://www.youtube.com/watch?v=rZcUcisuYSc
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