Question

Find the perimeter of each of the following shapes:
a) A triangle of sides 3cm, 4 cm, and 5 cm
b) An equilateral triangle of side 9 cm.
c) An isosceles triangle with equal sides 8 cm and third side 6cm.

Answer 1

Hint:Parameter of any shape is basically the center boundary of that shape.
The parameter of the triangle is the sum of its all sides. let us assumes sides of triangle area,b and c .hence,
\[perimeter{\text{ }} = a{\text{ }} + b{\text{ }} + c\]
Perimeter of an equilateral triangle is 3a because in equilateral triangle all sides are same.
The perimeter of an isosceles triangle two of its sides are the same
Therefore,

Complete step by step answer:

The perimeter of the triangle of sides 3cm,4cm and 5cm.
Perimeter of triangle\[ = \] sum of all sides
                                   \[ = {\text{ }}a + {\text{ }}b + c\] -----(1)
 Let a = 3cm, 4cm and c=5cm
 Using them in 1
We got p\[ = {\text{ }}3 + 4 + 5\]
\[ = {\text{ }}12cm\]
Perimeter of an equilateral triangle = \[3 \times side\]
Side of equilateral triangle =9cm
Hence, perimeter \[ = \] \[3 \times \]9
\[ = 27cm\]
Perimeter of an isosceles triangle with equal sides 8cm and third side 6cm is 2a +b
Let a =8 and b=6
 We have, perimeter =\[2 \times 8 + 6\]
\[ = 16 + 6\]
\[ = 22c{m_{}}\]

Note: Never confuse perimeter of a triangle with are of the triangle.
Hence, the perimeter is just the outer boundary of every triangle with its particular property.