Area of triangle ADE = (Area of DEBC) ⇒ Area of DEBC = 21 area of ΔABC So, Area of △ADEArea of △ABC = 12 The ratio of the area of two similar triangles is equal to the square of the ratio of their corresponding sides. So, (ADAB)2 = 12ADAB = 12ADAD+AB = 12
1 + ADBD = 12ADBD = 12−1ADBD = 12−1BDAD = 2−11 So, the required ratio = 1 : 2 - 1