how can we construct 4 equilateral triangles using 6 equal length sticks?

Answer 1

By using the six sticks to make the edges of a tetrahedron. Make one equilateral triangle with three of the sticks, then attach another stick to each corner of the triangle. Bring these three sticks up so their ends meet and fix them together. One tetrahedron, a three dimensional object with four faces, each of which is an equilateral triangle.

This would be so much easier of you could draw diagrams....

Answer 2

Its a triangle, with a smaller inverted triangle within it. The internal, inverted one having corners touching the outside rectange at a point midway along each length.

Answer 3

Make a pyramid.

Or, like the guy above calls it, a (3-dimensional) tetrahedron..

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