Select the most appropriate one-word substitution for the given words. a seven-sided figure
heptagon
Understanding Geometric Shapes: The Seven-Sided Figure
This question asks for the specific name of a polygon that has seven sides. Polygons are closed two-dimensional shapes made up of straight line segments.
Identifying the Seven-Sided Figure
The names of polygons are based on the number of sides they have. Different prefixes are used to indicate 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
Based on this list, a figure with seven sides is known as a heptagon.
Analyzing the Options for Seven-Sided Figures
Let's look at the provided options and determine the number of sides for each shape:
- Octagon: This prefix "octa-" means eight. So, an octagon is a figure with eight sides.
- Pentagon: This prefix "penta-" means five. A pentagon is a figure with five sides.
- Heptagon: This prefix "hepta-" means seven. A heptagon is a figure with seven sides.
- Hexagon: This prefix "hexa-" means six. A hexagon is a figure with six sides.
Comparing the definitions to the question, the term for a seven-sided figure is clearly heptagon.
Definition of a Heptagon
A heptagon is a polygon with seven sides and seven angles. A regular heptagon has all sides equal in length and all internal angles equal in measure. The sum of the interior angles of a heptagon is $(7-2) \times 180^{\circ} = 5 \times 180^{\circ} = 900^{\circ}$. In a regular heptagon, each interior angle measures $900^{\circ} / 7 \approx 128.57^{\circ}$.
Revision Table: Polygon Names
| Number of Sides | Polygon Name |
|---|---|
| 3 | Triangle |
| 4 | Quadrilateral |
| 5 | Pentagon |
| 6 | Hexagon |
| 7 | Heptagon |
| 8 | Octagon |
Additional Information on Polygons
Polygons are fundamental shapes in geometry. They are classified not only by the number of sides but also by other properties, such as whether they are convex or concave, regular or irregular.
- A convex polygon has no interior angles greater than $180^{\circ}$. All vertices point outwards.
- A concave polygon has at least one interior angle greater than $180^{\circ}$. At least one vertex points inwards.
- A regular polygon is both equilateral (all sides equal) and equiangular (all angles equal).
- An irregular polygon is one that is not regular; its sides and angles may vary.
The question specifically asks for the name based on the number of sides, which is the primary classification method for basic polygons like the seven-sided figure.
Important Questions from One Word Substitution
Select the option that can be used as a one-word substitute for the given group of words.
A glass container to keep fish
Select the option that can be used as a one-word substitute for the given group of words.
Something that is strong and lasts a long time without breaking or becoming weaker.
Select the word which means the same as the group of words given.
A place where plants are grown for sale
In the following question, out of the four alternatives, choose the one which can be substituted for the given words/sentence.
Open refusal to obey orders
Select the word which means the same as the group of words given.
A doctor who specializes in heart diseases
