Question

1. choose the correct answer.

a(n)_____ is a closed plane figure formed by three or more line segments, such that each segment intersects exactly two other segments only at their endpoints, and no two segments with a common vertex are collinear.
vertex of a polygon
polygon
diagonal of a polygon
side of a polygon

1. choose the correct answer.

a(n)_____ is the common endpoint of two sides of a polygon.
vertex of a polygon
side of a polygon
equiangular polygon
polygon

Explanation:

For the first question, a polygon is defined as a closed - plane figure formed by three or more line segments with the given intersection properties. A vertex is a point, a diagonal is a line segment connecting non - adjacent vertices, and a side is a single line segment.
For the second question, by definition, the common endpoint of two sides of a polygon is called a vertex. A side is a line segment, an equiangular polygon is a type of polygon with equal angles, and a polygon is the whole figure.

Answer:

1. polygon
2. vertex of a polygon