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If the number of sides of a regular poly...

If the number of sides of a regular polygon is n, then the number of lines of symmetry is equal to

A

2n

B

n

C

`(n)/(2)`

D

`n^(2)`

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AI Generated Solution

The correct Answer is:
To determine the number of lines of symmetry in a regular polygon with \( n \) sides, we can follow these steps: ### Step-by-Step Solution: 1. **Understanding Lines of Symmetry**: A line of symmetry is a line that divides a shape into two identical parts that are mirror images of each other. For regular polygons, these lines can pass through vertices or the midpoints of sides. 2. **Identifying the Regular Polygon**: A regular polygon is defined as a polygon with all sides and angles equal. Examples include an equilateral triangle, a square, and a regular pentagon. 3. **Counting Lines of Symmetry**: - For a regular triangle (3 sides), there are 3 lines of symmetry. Each line passes through a vertex and the midpoint of the opposite side. - For a square (4 sides), there are 4 lines of symmetry. Two lines pass through opposite vertices, and two lines pass through the midpoints of opposite sides. - For a regular pentagon (5 sides), there are 5 lines of symmetry. Each line passes through a vertex and the midpoint of the opposite side. 4. **Generalizing the Pattern**: From the examples above, we can see that for any regular polygon with \( n \) sides, there are \( n \) lines of symmetry. This is because: - Each vertex can be connected to the midpoint of the opposite side, and there are \( n \) vertices in total. - Additionally, lines can be drawn through the midpoints of opposite sides, but since it’s a regular polygon, the symmetry remains consistent with the number of sides. 5. **Conclusion**: Therefore, the number of lines of symmetry in a regular polygon with \( n \) sides is equal to \( n \). ### Final Answer: The number of lines of symmetry in a regular polygon with \( n \) sides is \( n \). ---
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ARIHANT PUBLICATION PUNJAB-GEOMETRY-CHAPTER EXERCISE
  1. The number of lines of symmetry of the figure is

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  2. In Delta PQT, PQ = PT. The points R and S are on QT such that PR = PS....

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  3. If for ∆ABC and ∆DEF, the correspondence CAB ↔ EDF gives a congruence,...

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  4. A polyhedron has 30 edges and 12 surfaces. How many vertices of this p...

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  5. In Delta PQR, PQ = 4cm, PR = 6 cm and QR =3 cm. Which of the following...

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  6. In Delta ABC and Delta LMN, AB=LM, AC = LN and angle B = angle M. Then...

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  7. A polyhedron has 6 faces and 8 vertices. How many edges does it have?

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  8. The sum of all interior angles of a polygon is 1440^(@). The number of...

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  9. If one of the angles of a triangle is 130^(@) , then the angle between...

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  10. In a quadrilateral ABCD, angle D=60^(@) and angle C = 100^(@). The bis...

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  11. The sum of all interior angles of a regular polygon is 1080^(@). What ...

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  12. In Delta DEF and Delta PQR, if PQ =DE, EF=PR and FD =QR, then

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  13. The interior angle of a regular polygon is 156^0dot Find the number of...

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  14. If the number of sides of a regular polygon is n, then the number of l...

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  15. In which one of the following cases, the construction of a quadrilater...

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  16. Let x be the angle which is equal to its complement and y be the angle...

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  17. How many sides has a regular polygon, each angle of which is of mea...

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  18. The angles of a quadrilateral are in the ratio 2:3:5:8. The sum of the...

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  19. If one angle of a triangle is 110^(@), then the angle between the bise...

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  20. In Delta ABC, AB= 4cm, AC = 5 cm and BC = 6 cm. In Delta PQR, PR = 4 c...

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