Question

find the area of an equilateral triangle with an apothem 3.5 meters long and each side 12 meters long.

Answer 1

A=b*h/2

Answer 2

1}126 m
2}84 m
3}63 m
4}42 m

Answer 3

\[\text{Area}=\frac{s^2n}{4 \text{Tan}\left[\frac{\pi }{n}\right]} \]Where n is the number of sides and s is the side length of a regular polygon. For this equilateral triangle, s=12 and n=3.\[\text{Area}=36 \sqrt{3}=62.4\]3} is the nearest value to the calculated area.

http://www.mathopenref.com/polygonregulararea.html

Answer 4

\[\text{Area}=a^2n \text{Tan}\left[\frac{\pi }{n}\right] \]Where n is the number of sides and a is the apothem of a regular polygon. The expression evaluated with a=3.5 and n=3 yields an area of 63.7 or 64 rounded.