posted by ben .
Find the area of an equilateral triangle (regular 3-gon) with the given measurement.
A = sq. in.
Draw a straight line from the mid point of one side to the opposite vertex.
Use the Pythagorean Theorem to find the length of this line. Let b = this line (the height).
a^2 + b^2 = c^2
3^2 + b^2 = 6^2
9 + b^2 = 36
b^2 = 27
b = 5.2
Now use this formula to find the area of this triangle.
A = 1/2bh
In en.wikipedia type:
You will find everything about equilateral triangle
What is the area of a equlateral triangle with the measurement of 6-inch side?