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Question:

A kite in the shape of a square with a diagonal 32 cm and an isosceles triangle of base 8 cm and sides 6 cm each is to be made of three different shades as shown in figure. How much paper of each shade has been used in it?

Solution:

Given: Diagonal = 32 cm, Base = 8 cm, side = 6 cm
→Area of square = 1/2 × (d)² = 1/2 × (32)² = 512 cm²
→Area of shaded portion I = Area of shaded portion II
→512/2 = 256 cm²
∴Area of paper required for I and II = 256 cm²
→For triangle III region
→S = (6 + 6 + 8)/2 = 10 cm
→A = √s(s-a)(s-b)(s-c) →Area = √10(10-6)(10-6)(10-8) = √10 × 4 × 4 × 2 cm²
→A = 4√20 cm² = 17.89 cm² ≈ 17.92 cm²
Area of paper required for III triangle shade = 17.92 cm²