I draw a square on the sand. On each of its sides, I put a stone.
Two days later, the stones didn't move, but the wind has blown away the square.
Could you find again the square, given the stones ?
Now I put the stones on the lines
containing the sides.
New : The points are replaced by circles touching the square's sides
(That is to construct a square whose sides are tangent to 4 given circles)
And also : the square is replaced by a golden rectangle (ratio of sides = φ = (1 + √5)/2)
Now the inverse problem :
I draw 4 points at the vertices of a square on a paper.
Then I draw 4 lines going through these points.
Unfortunately, the lines having the same colour as the points, I can't see my points anymore !
And of course I didn't draw the square itself...
Could you find it ?