Find the unknown length 'Z' of the following figure when BC = 4 cm, CD = 3 cm, and ED = 13 cm.
8 cm
When two chords of a circle intersect internally or externally, then the products of the lengths of segments are equal.
AC×BC=DC×EC
(Z + 4) (4) = 3×(13+3)
(Z+4)=3×164
Z + 4 = 12
Z = 12 - 4
Z = 8