hendecagon
It is a quadrilateral
A quadrilateral is a closed plane figure with four straight sides.
A rectangle is a plane figure with four straight sides and four right angles. Generally considered to have unequal adjacent sides to differ them from squares.
A polygon
A quadrilateral - if the sides are straight lines.
A plane figure with three straight sides and three angles.
It is a quadrilateral
A polygon is a plane figure with 3 or more straight sides and angles. A plane figure is a flat enclosed figure made of straight lines, curved lines, or both.
A polygon.
A rectangle is a plane figure with four straight sides and four right angles, esp. one with unequal adjacent sides. A square is a plane figure with four equal straight sides and four right angles. A rhombus is a parallelogram with opposite equal acute angles, opposite equal obtuse angles, and four equal sides.
A quadrilateral is a closed plane figure with four straight sides.
A Polygon is a closed plane figure bounded by straight sides.Polygons is a plane figure with more than 3 straight sides and angles and are typically 5 or more.
A polygon is a plane figure with at least three straight sides and angles, so a triangle qualifies.
A hexagon has six sides and six angles.
a decagon
Triangle is plane with three sides and three angles. The sum of its inside angles is equal to 180 degrees.
A plane figure with at least three straight sides and angles, and typically five or more.