I have 3 sides, what am I?
Triangle
I have 4 sides, what am I?
Quadrilateral
I have 5 sides, what am I?
Pentagon
I have 6 sides, what am I?
Hexagon
I have 7 sides, what am I?
Heptagon
I have 8 sides, what am I?
Octagon
I have 9 sides, what am I?
Nonagon
I have 10 sides, what am I?
Decagon
I have 11 sides, what am I?
Hendecagon
I have 12 sides, what am I?
Dodecagon