The diagram shows a sequence of three squares made with matches. Work out the rule to give the number of matches needed to make the nth square in the sequence.

Answer:
below
Step-by-step explanation:
Notice that each time we add a an odd number of squares to create a new square
each time we add an odd number we create a perfect square
a perfect square.
A perfect square is written as:
to get the first square we replaced n with 1, to get the second one we replaced it with two and so on ...
So the formula is: