SOLUTION: Find the area of an equilateral triangle (regular 3-gon) with the given measurement.
9-inch perimeter
A = sq. in.
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Polygons
-> SOLUTION: Find the area of an equilateral triangle (regular 3-gon) with the given measurement.
9-inch perimeter
A = sq. in.
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You can put this solution on YOUR website! All three sides of an equilateral triangle are equal, then
:
9/3 = 3 inches for each side
:
use Pythagorean Theorem to finc the height(h)
:
h^2 + (3/2)^2 = 3^2
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Note the height bisects the base
:
h^2 = 9 -9/4 = 27/4
:
h = 3 * square root(3) / 2
:
Area = (1/2) * 3 * (3 * square root(3) / 2) = 9 * square root(3) / 4
:
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Area of triangle is 3.8971 square inches
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