Find the area of equilateral triangle whose side is 12 cm using H… - Vidyadip

Question

Find the area of equilateral triangle whose side is $12 \ cm$ using Heron's formula.

✓

Answer

in equilateral triangle, all sides are equal.
let`s sides are $a =12$
$S =\frac{12+12+12}{2} \ cm$
$=\frac{36}{2} \ cm$
$=18 \ cm$
$\therefore$ Area of equilateral $=\sqrt{ s ( s - a )( s - b )( s - c )}$
$=\sqrt{18(18-12)(18-12)(18-12)}$
$=\sqrt{18 \times 6 \times 6 \times 6}$
$=36 \sqrt{3} sq \ cm $

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