Can the plane be "tiled": a) with triangles equal to a given one; b) with quadrilaterals equal to a given one?
The source for this one didn't record the answer, so there is nothing to check what you type against. Work it on paper and mark yourself against the solution below.
61. It is not difficult to prove that the diagonals of this quadrilateral serve as the bisectors of its angles, and such a convex quadrilateral is a rhombus.
62. a) possible, c) possible.
Source: NuminaMath-1.5,
licensed Apache-2.0.
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