Q4 of 15 Page 202

Find the area of a triangle two sides of which are 18cm and 10cm and the perimeter is 42cm.

Two sides of the triangle are 18cm and 10cm (Given)

Parameter of the triangle = 42 cm


Third side of triangle = 42 – (18 + 10)


= 14cm


Semi perimeter of triangle(s) =


= 21cm


Using Heron’s formula,


Area of the triangle =


=


=


=


= cm2


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