Triangle ABC is isosceles with AB=BC. If AC = 20 and [ABC] = 240, then find the perimeter of triangle ABC.
We can work out that the height of triangle ABC is 32. So the perimeter of triangle ABC is 94.
ABC area is 240 u² AC = 20
Height H = 240/ (20/2) = 24
AB = sqrt[( 10² + 24²) = 26 AB = BC
Parameter P = AB + BC + AC = 72
