Question

If the perimeter of an equilateral triangle is 36cm gind its area

Answer 1

Answer:

36√3 square metres.

Explanation:

Let the side of an equilateral triangle = a cm

i ) perimeter = 36 cm ( given)

=> 3a = 36

=> a = 36/3

=> a = 12 cm

ii ) Area of the triangle

= (√3/4 )a²

= (√3/4) × 12²

= √3 × 36

= 36√3 square metres.

••••

Answer 2

$\bf\huge\textbf{\underline{\underline{According\:to\:the\:Question}}}$  

Suppose the side of an equilateral triangle be p cm

Perimeter = 36 cm

⇒ 3p = 36

$\bf\huge{\implies p =\dfrac{36}{3}}$        

⇒ p = 12 cm

Area of equilateral triangle (Assume p = a)

$\bf\huge{\implies\dfrac{\sqrt{3}}{4}\times a^2}$  

$\bf\huge{\implies\dfrac{\sqrt{3}}{4}\times (12)^2}$

= √3 × 36

= 36√3 sq m