Q25 of 69 Page 240

If the base of an isosceles triangle is 6cm and its perimeter is 16cm, then its area is 12cm2.

It is given in the question that,

Base of the triangle, b = 6 cm


Equal sides of the isosceles triangle = a cm


Perimeter = 16 cm


We know that,


Perimeter = Sum of all sides


16 = a + a + 6


16 = 2a + 6


2a = 10


a =


a = 5 cm


∴ Area of an isosceles triangle =


=


= 1.5 ×


= 1.5 ×


= 1.5 × 8


= 12 cm2


Hence, the given statement is true


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