The lengths of three consecutive sides of a quadrilateral circumscribing a circle are 4 cm, 5 cm and 7 cm respectively. Determine the length of the fourth side.
Given
AB = 7, BC = 5, CD = 4
Length of the tangent drawn from an external point to the circle are equal
Therefore
AB = CD = BC + AD
7 + 4 = 5 + AD
AD = 11 - 5 = 6
