The sum of the angles in the four segments exterior to a cyclic quadrilateral is equal to `6` right angles.

Explanation

APBS iis a cyclic quadrilateral

`/_1+/_P=180^@-(1)`

BQCS is a cyclic quadrilateral

`/_2+/_Q=180^@-(2)`

CRQS is a cyclic quadrilateral

`/_3+/_R=180^@-(3)`

`/_P+/_Q+/_1+/_2+/_R+/_3=3*180^@`

`/_P+/_Q+/_R+/_1+/_2+/_3=3*180^@`

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