Where can you put the mirror across the square so
that you can still 'see' the whole square?
How many different positions are possible?
How many lines of symmetry does a square have?
Can you reflect part of the square so that you can
see a smaller square?
A rectangle? A kite? A hexagon? An octagon?
What do all the shapes have in common?
This problem is taken from 'Starting from Mirrors' by David Fielker, published by BEAM Education. It can be purchased from the BEAM website.