M l aggarwal understanding icse mathematics class 8 Solutions for Chapter 16 symmetry reflection and rotation

Fill in the blanks:

(i) A figure has ………….. symmetry if it is its own image under a reflection.

(ii) A kite has ………….. line(s) of symmetry.

(iii) A parallelogram has ………….. line(s) of symmetry.

(iv) The center of rotation of an equilateral triangle is the point of intersection of its

…………..

(v) The center of rotation of a rhombus is the point …………..

(vi) A regular polygon of n-sides has ………….. the number of lines of symmetry.

(vii) Angle of rotational symmetry in an equilateral triangle is …………..

(viii) Angle of rotational symmetry in a regular pentagon is …………..

(ix) If after a rotation of 45° about a fixed point the figure looks exactly the same,

then the order of rotational symmetry is …………..

The figure which does not have both line and rotational symmetry is

possible angle of rotation of a figure having rotational symmetry of order

greater than or equal to 2 is

(a) 36°

(b) 144°

(c) 150°

(d) 360°

The letter which has both line and rotational symmetry is

(a)H

(b)M

(c) S

(d)Y

Draw the line or lines of symmetry, if any, of the following shapes and count their

number:

For each of the given shape in question 1, find the order of the rotational symmetry (if any).

Construct a rectangle ABCD such that AB = 4.5 cm and BC = 3 cm. Draw its line (or lines) of symmetry.

Construct a rhombus ABCD with AB = 5.3 cm and ∠A = 60°. Draw its line (or lines) of symmetry.