The surface area of the tetrahedron is simply four times the area of a single equilateral triangle face:
[tex]A=\frac{1}{4}\sqrt{3} *a^2[/tex]
The tetrahedron has 4 equal triangle faces, so the total surface formula is:
[tex]S=4A= \sqrt{3}*a^2[/tex], where [tex]a[/tex] represents length of triangle's side.
