10. Prove the Two Secant Segment Theorem. Two Secant Segment Theorem: If two secant segments are drawn to a circle from an external point, then the product of the lengths of one of the secant segments with its external portion is equal to the product of the secant length of the other with its external portion. In the diagram below AD is a secant segment with external portion AB, and AE is a secant segment with external portion AC, and you need to prove that (AD)(AB) = (AE)(AC).