Question:-
Find the area of an equilateral triangle with side length = 9cm correct upto one decimal place.
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Solution:-
In an equilateral triangle all sides are equal.
Let s = side length = 9 cm
Then, area of equilateral triangle is given as:
A = (√3/4)s²
Putting the value of s here,
A = (√3/4) * (9 cm)²
=> A = (√3/4) * 81 cm²
=> A = √3 * 20.25 cm²
We know that, √3 = 1.732
=> A = 1.732 * 20.25 cm²
=> A = 35.073 cm²
Rounding to one decimal place,
=> A = 35.1 cm²
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