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2 years ago

If the perimeter of an equilateral triangle is 30cm, find its area.

Mathematics

1 answer:

lora16 [44]2 years ago

7 0

Answer:

A ≈ 43.3 cm²

Step-by-step explanation:

the area (A) of an equilateral triangle is calculated as

A = $\frac{s^2\sqrt{3} }{4}$ ( s is a side of the triangle )

given perimeter = 30 cm , then

s = 30 cm ÷ 3 = 10 cm

then

A = $\frac{10^2\sqrt{3} }{4}$ = $\frac{100\sqrt{3} }{4}$ = 25 $\sqrt{3}$ ≈ 43.3 cm² ( to the nearest tenth )

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3 years ago

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If the perimeter of an equilateral triangle is 30cm, find its area. ​

If the perimeter of an equilateral triangle is 30cm, find its area.