A pentagon has five sides and five angles, the only 2-D shape with these characteristics.
How about a triangle which is a 2 dimensional shape with 3 sides
A quadrilateral is a 2D shape that has 4 sides
A 2-D shape with seven sides is called a HEPTAGON.
A dodecagon has 12 sides.
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A square
Hexagon
Nonagon
In 2-d, a heptagon.
A 9-sided shape is known as a nonagon.
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