Page 235 - Ganit Kaushal

2. The Eyes

What does this figure look like at first glance?
Eyes. Absolutely right.
Can you draw it with a ruler and compass?
Yes, we can.

Let us learn to draw this artwork, ‘Eyes’, with the help of a ruler and compass.
Construction 13: Draw the ‘eyes’ with a compass and ruler,
making a good estimate of measurements. (NCERT) Note

Sol. Follow the given steps to construct the artwork ‘Eyes’. In geometric constructions, one often
Step 1: Draw two straight lines, PQ and RS, each 4 cm constructs supporting curves or
long and 1 cm apart. figures that are not part of the given
figure but help in constructing it. Here
P Q R S PQ and RS are supporting lines as
Step 2: Set the distance equal to 4 cm between the legs they are not part of the construction.
of the compass. Put the pointer at P and draw two small
arcs on both sides of PQ. Now, without changing the setting of the compass, put the pointer at Q
and draw two arcs that cut the previous arcs at points A and B respectively as shown in the adjoining
figure (i). Obviously, points A and B are equidistant from points P and Q.
Step 3: Similarly, we can find
points C and D that are A D A D
equidistant from points R and S.
[see figure (i)]
Step 4: With the same compass P Q R S P Q R S
setting, now put the pointer at A
and pencil lead at P, and draw
an arc that passes through Q B C B C
( A is equidistant from P and (i) (ii)
Q) as shown in the figure (ii). Similarly, by putting the pointer at points B, C and D, we can draw three
more such arcs to get the figure required for the A D
eyes as given in figure (iii).
Step 5: Remove all the supporting curves and
arcs. Make the eyeballs with the help of the
pencil to get the perfect shape of the eyes, as P Q R S P Q R S
shown in figure (iv).
We have got the perfect shape for the eyes, isn’t B C
it? If not, then try again with a good estimate. (iii) (iv)

3. The Wavy Waves
Upper wave
Now, we will learn to construct a Wavy Wave, as shown in the adjoining figure, B
when the central line AB is of a given length. A Central line

Lower wave
Wavy wave

Playing with Constructions 233