Q. 34.1( 46 Votes )

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

Answer :

Let the third side of the triangle is

Since the perimeter of a triangle is given by:

cm

Let a, b and c are the sides of triangle and s is the semi-perimeter, then its area is given by:

A = where [Heron’s Formula]

= = 21

A =

A = = cm^{2}

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