Question

side of an equilateral triangle is 20cm what will be it's area​

Answer 1

use formula to find area

a= √3/2

Answer 2

AnsWer :

100√3 cm²

SolutioN :

★ Diagram.

$\setlength{\unitlength}{0.78 cm}\begin{picture}(12,4)\thicklines\put(5.4,5.8){ B }\put(11.2,5.8){ C }\put(8.4,10){ A }\put(6,6){\line(2,3){2.5}}\put(11,6){\line(-2,3){2.5}}\put(6,6){\line(1,0){5}}\put(5,7.9){ a\:cm }\put(11,7.9){ a\:cm }\put(8,5){ a\:cm }\end{picture}$

$\tt \dagger \: \: \: \: \:\fbox{Area \: of \: Equilateral_{\triangle} = \frac{ \sqrt{3} }{4} {a}^{2}}$

Where as,

• a sides of Equilateral triangle.

✎ Now, Putting the given value.

$\tt Area \: of \: Equilateral_{\triangle} = \frac{ \sqrt{3} }{2} {(20)}^{2}$

$\tt : \implies \frac{ \sqrt{3} }{4} \times 400.$

$\tt : \implies \sqrt{3} \times 100.$

$\tt : \implies 100 \sqrt{3} \: cm^2.$

♢ Therefore, the area of Equilateral triangle is 100√3 cm².

$\rule{90}2$

Some Information :

• In Equilateral triangle.
• Each Sides same.
• Each angle 60°.
• Number edges 3.
• Number of Vertices 3.
• Perimeter 3 * Sides.