Draw a diagonal across a square, as illustrated, a bisected right angle has two equal angles, 45 and 45. I would guess it was instead meant to represent the angle from the base of the formed tetrahedron along one of its three sides to the apex ... unless this is not a cube but a rectangular block (rectangular cuboid.)
Hmmm the puzzle last day or so was refined [1] ... However this time around it's clear that the puzzle is in the realm of non euclidean maths, since the bottom left side of the explanatory sketch, placers a right angle and two red angles of 54.74 making a triangle on the face of the cuboid -- 3 internal angles of 90 + 54.74 +54.74 is greater than 180 degrees. Euclidean geometry on the other hand, the internal angles of a triangle sum to equal 180.
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