Find the perimeter of each of the following shapes :
(a) A triangle of sides $ 3 \mathrm{~cm}, 4 \mathrm{~cm} $ and $ 5 \mathrm{~cm} $.
(b) An equilateral triangle of side $ 9 \mathrm{~cm} $.
(c) An isosceles triangle with equal sides $ 8 \mathrm{~cm} $ each and third side $ 6 \mathrm{~cm} $.
To do:
We have to find the perimeter of each of the given shapes.
Solutions:
We know that,
Perimeter is defined as the length of the outline of a shape.
To find the perimeter of a shape, just add the lengths of all the sides of the shape.
Therefore,
(a) The perimeter of the triangle whose sides are $3\ cm, 4\ cm$ and $5\ cm= 3\ cm+4\ cm+5\ cm$
$=12\ cm$
(b) The perimeter of the equilateral triangle of side $9\ cm=3\times$ Length of the side.
$ = 3\times9$
$ =27\ cm$
(c) The perimeter of an isosceles triangle with equal sides $8\ cm$ and third side $6\ cm =8\ cm+8\ cm+6\ cm$
$ =22\ cm$.
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