# Number of sides a regular polygon has.

The question is "Both tile A and B are regular polygons. Work out the number of sides A has."

For this I put B is equilateral ∴ all angles are 60.

However, I have no idea where to go from this.

Could anyone give me any tips for solving this and similar questions? Thanks.

Hint Look around a $60^\circ$ angle. You see a $60^\circ$ angle of tile $B$ and two angles of tile $A$. So what is the angle of tile $A$?
What is the angle between two sides of a regular $n$-gon? For which $n$ is exactly the above value?