Question

The perimeter of an isosceles triangle is 3.6 m and its base is 30 cm shorter than each of the equal sides. What is the area (in m2) of the triangle?
1. 0.72
2. 0.8
3. 0.54
4. 0.6

Answer 1

Correct Answer - Option 4 : 0.6

Given:

Perimeter of isosceles triangle = 3.6m

Formula:

a = equal side and b = unequal side

Area of isosceles triangle = b/2 × √(a² - b²/4)

Calculation:

⇒ b = a - 0.3

⇒ 3.6 = 2a + b

⇒ 3.6 = 2a + a - 0.3

⇒ a = 1.3 m

b = 1.3 - 0.3 = 1m

Area of isosceles triangle = 1/2 × √(1.3² - 1²/4) = 0.6 m²

∴ Area of an isosceles triangle is 0.6 m²