The segments AC and BD intersect at point O. Prove the equality of triangles BAO and DCO

The segments AC and BD intersect at point O. Prove the equality of triangles BAO and DCO if it is known that the angle BAO = the angle DCO and AO = CO.

Triangles BAO and DCO are equal in the second sign of equality of triangles: in side and two adjacent corners. According to the condition: angle BAO = angle DCO, AO = CO.

The angle AOB is equal to the angle DOC – vertical angles.



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