If two secants are drawn from a point lying outside a circle, then the product of one secant on its outer part is equal to the product of the other secant on its outer part.
DE*CE = AE*BE
DE = CD + CE = 1 + x + 4 = x + 5 AE = AB + BE = 11 + x + 1 = x + 12
What you have to find is LCM(least common multiple in order to find the lcm all you have to do is list all the multiples and find their common multiple.
