a baseball field has four bases that form the shape of a quadrilateral. If someone invented a new game similar to baseball that had an extra base in the field, what type of polygon would the base form?

pentagon
octagon
decagon
hexagon

5 sides is a pentagon

6 is hex
8 is octa
10 is deca

To determine the type of polygon that would form with five bases in a baseball field, you need to understand the relationship between the number of sides and the corresponding polygon name.

A polygon is a closed shape that has straight sides. The number of sides in a polygon determines its name. Here are the names of polygons based on the number of sides:

- Three sides: triangle
- Four sides: quadrilateral
- Five sides: pentagon
- Six sides: hexagon
- Seven sides: heptagon
- Eight sides: octagon
- Nine sides: nonagon
- Ten sides: decagon

In a baseball field, there are currently four bases, forming a quadrilateral. If someone were to add an extra base to the field, there would be five bases in total. Since five sides make a pentagon, the extra base would form a pentagon shape.

Therefore, the answer to your question is a pentagon.

If a new game similar to baseball had an extra base on the field, the bases would form a pentagon.