Tetrahedron has side lengths , and . The distance from vertex to face can be written as , where are positive integers, is square-free, and . Find .
Solution
First, we see that faces , and are all right triangles. Now, can be visualized as the base, and it can be seen that side is then the height of the tetrahedron, as should be perpendicular to both and . Therefore, the area of the base is and the volume of the tetrahedron is . Now, let the height to be . The area of triangle comes out to . This means that the volume is
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