Given circle Γ and a point P outside of Γ, 2 lines l1 and l2 are drawn such that both pass through P. l1 intersects Γ at A and B, and l2 intersects Γ at C and D, with C between D and P. If PA=44,PB=294 and PC=56, what is PD?
Use the property of intersecting chords
PA*PB=PC*PD
In this case the chords intersect outside of Γ.
Also, if T is the tangent to Γ passing through P, then
PA*PB=PC*PD=PT²