Q. 54.3( 22 Votes )

# Find the area of a triangle two sides of which are 4 cm and 8 cm and the perimeter is 20 cm.

Answer :

**Given:** Perimeter of triangle = 20 cm

Two sides of triangle = 4 cm and 8 cm

To Find: Area of the triangle

**Concept Used:**

If sides of a triangle are a, b, and c, then area of a triangle is given by:

Where s = semiperimeter of the triangle

The perimeter of triangle = Sum of sides of the triangle

**Assumption:** Let the sides of the triangle be, a, b, and c such that

a = 4 cm, b = 8 cm and a + b + c = 20 cm

**Explanation:**

a + b + c = 20 cm

4 + 8 + c = 20

12 + c = 20

c = 8 cm

s = 10 cm

Area = 4√15 cm^{2}.

**Hence, the area of the triangle is 4√15 cm ^{2}.**

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