Centroid, incenter, circumcenter and orthocenter are collinear ⇒ Triangle is isosceles ⇒ two sides must be equal. AB is the longest side⇒ the other two sides must be equal Sides should be 8, y and y. Perimeter = 8 + 2y, s = 4 + y Area=√(4+y)(y−4)(4)(4) 24=√42(y2−16) 24=4√y2−16 6=√y2−16 y2=52 ⇒y=√52 y=2√13 Perimeter=8+2y=8+4√13