Page 250 - Ganit Kaushal

Ex 3. Given the line(s) of symmetry, find the other hole(s): (NCERT)

(a) (b) (c)

(d) (e)

Sol. The other hole is shown in red colour for identification.

(a) (b) (c)

(d) (e)

Ex 4. How many lines of symmetry do these shapes have? (NCERT)

Sol. The lines of symmetry are shown by the dotted lines.

There are 4 lines of symmetry. There are 8 lines of symmetry.
Ex 5. Suppose you have to get each of these shapes with some folds and a single straight cut. How will you
do it? (NCERT)
The hole in the centre is a square as shown in the following two figures:

(a) (b)

Sol. (a) To get such a square at the centre, fold the square paper twice along the two diagonal
lines of symmetry, as shown. Then, a single straight cut will create such a square
at the centre on unfolding the paper.
(Students are advised to do this as an activity.)

248 Mathematics-6