Answer:
AB = AC
BD CE
AB/8 = 18/12
AB = 12
(AB)2 + (BC)2 = (AC)2
(12 )2 + (BC)2 = (18)2
144 + (BC)2 = 324
(BC)2 = 180
BC = √ 180 = 6 √ 5
Therefore, the perimeter of ∆ABC = 12 + 6 √ 5 + 18 =
