NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 9: Symmetry and Practical Geometry - Fill in the Blanks
Question 26

Question. 26

The number of lines of symmetry in Fig. 9.11 is ____.

Fig 9.11

Answer:

5.

Detailed Answer with Explanation:

  1. Look at the picture. It is a rosette (flower-like shape) with five petals. All petals look the same and are placed evenly around the centre.
  2. What is a line of symmetry? It is a straight line that cuts a shape into two equal mirror halves. If you fold the shape on this line, both halves match exactly.
  3. How to find symmetry lines here? For shapes made of equal parts around a centre, the number of symmetry lines equals the number of equal parts.
  4. Count the equal parts (petals).
    5. \[ ext{Number of petals} = 5\]
  5. So, the number of symmetry lines is also 5.
    6. \[ ext{Lines of symmetry} = 5\]
  6. Where are these lines? Draw a straight line from the centre through the middle of each petal. Each such line is a mirror line.
  7. Quick check (fold or mirror test): If you fold the rosette along any of these lines, one half will lie exactly over the other half. That means each line is a line of symmetry.
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