Q13 of 33 Page 12

The perimeter of an isosceles triangle is 42 cm, and its base is (3/2) times each of the equal sides. Find the length of each side of the triangle, the area of the triangle.

Given: Base of an isosceles triangle = (3/2) times of equal sides and perimeter = 42 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



Assumption:


Let the equal sides of the triangle be ‘a’ cm.


Explanation:



Perimeter = 42





a = 12 cm


Therefore, the sides of the triangle are 12 cm, 12 cm, and 8 cm.




s = 21 cm


Now,




Area = 9√273 cm2


Hence, the area of the triangle is 9√273 cm2 .


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