Draw an equilateral triangle in such a way that its vertices lie on three given straight lines, which are in the same plane and equidistant from each other.
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We bring the three lines into a parallel position with some plane (for example, the second one), and by constructing the equilateral triangle (K. M. L. VII. 86. page) we restore it to its original plane.
(Tóbiás J. László.)
The problem was also solved by: Pintér Miksa.
Source: NuminaMath-1.5,
licensed Apache-2.0.
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