SOLUTION: An equilateral triangle has 27 cm. What is its area? Thank you.

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Question 1011926: An equilateral triangle has 27 cm. What is its area? Thank you.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
Each side is 27%2F3=9 cm.

An altitude separates two congruent special right triangles. The altitude serves as height and the hypotenuse is also 9 cm. The short leg will be half the hypotenuse, or 9%2F2.

You want an area 2%281%2F2%29%289%2F2%29%2Ay, using y as the altitude. The factor 2 is used on the far left because TWO of the special 30-60-90 right triangles make your given one equilateral triangle.

find y using pythagorean theorem formula.
y%5E2%2B%289%2F2%29%5E2=9%5E2

Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
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An equilateral triangle has 27 cm. What is its area?
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Read your post. It says:

"An equilateral triangle has 27 cm."

What is 27 cm ???????

The side, the perimeter, the height? What ??

Edit and re-submit.