Q6 of 15 Page 202

An isosceles triangle has perimeter 30 cm and each of the equal sides is 12 cm. Find the area of the triangle.

Length of equal sides of the triangle = 12cm

Parameter of the triangle = 30 cm


Third side of triangle = 30 – (12 + 12)


= 6cm


Semi perimeter of triangle(s) =


= 15cm


Now,


Using Heron’s formula,


Area of the triangle =


=


=


= cm2


Hence, the area of triangle is cm2


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