D1. SQUARE DEAL    

Move just one of the matches at right to make a square.







 

• There has to be a trick here somewhere! Perhaps the sought after square is not bounded by matches?

• Look carefully at the placing of the matches. Is there anything unusual here?

       

The square appears in the centre.

In fact there is another interesting solution here.
The right hand match can be rotated and placed
to make the numeral 4 – a perfect square!
Unfortunately my page technology does not allow
this to be done online.