The procedure followed in teaching the concept of bisector of an angle is to be
repeated as it is. Now the child may be allowed to explore the angle bisector, which
enables the child to realize that the angle bisector facilitated the formation of two
angles with a common arm, and hence such angles are called as adjacent angles.
- Vertically opposite angles
The angles formed by the intersection of two lines and which are not adjacent angles
are called as the vertically opposite angles. In other words, when two lines intersect
they form two pairs of angles. The angles which are opposite to each other are called
as vertically opposite angles. Note that, the measurement of two vertically opposite
angles is always equal.
Provide the child with a sheet of paper, which has been folded to form two intersecting
lines in it. Facilitate the child to explore the nature of the four angles formed therein.
Now explain to the child that the two pairs of vertically opposite angles formed by
the intersection of any two lines will always be equal. The child may be facilitated to
measure the equal angles which may enable him/her to understand that the vertically
opposite angles are always equal.
- Transversal
A line which divides two other lines at two different points is called as the transversal.
If the two lines happen to be parallel to each other then the transversal forms a
number of equal angles.
1
5
2
6
3
7
4
8
A
C B
D
O