"intersect" is referenced in the pages listed below.
The angle made by two secants that intersect outside a circle is half the difference between the intercepted arc measures.
Definition of the intersection of two lines
Determining where two straight lines intersect in coordinate geometry
States: When two secant lines intersect each other outside a circle, the products of their segments are equal.
States: When two chords intersect each other inside a circle, the products of their segments are equal.
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