Given three non-collinear points D, E and F, construct triangle ABC containing these points in its sides and such that the division-ratios of the sides, by these points are given.
Extend DE by EL, such that DE/LE = AE/EC (given). L is constructible. Similarly extend FD by FN, such that FD/FN = FB/FA (given). N is constructible. Similarly K, J and M, O are constructible. Thus triangle GHI is constructible.