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Example Question #1 : How To Find The Length Of An Edge Of A Tetrahedron
Refer to the above tetrahedron, or four-faced solid. The surface area of the tetrahedron is 444. Evaluate to the nearest tenth.
The tetrahedron has four faces, each of which is an equilateral triangle with sidelength . Since the total surface area is 444, each triangle has area one fourth of this, or 111. To find , set in the formula for the area of an equilateral triangle: