Two identical twelve-inch rulers on a desk form an isosceles triangle with included angle . If Mickie moves the rulers so that increases at the rate of 2.5 radians per second, what is the rate of change of the area of the triangle when = /4 radians? Two identical 12-inch rulers form an isosceles triangle with an included angle theta. The area of the triangle is shaded in. Note: the area of an isosceles triangle with legs of length l and included angle is given by the formula A = 1 2 l 2 sin