Understanding: Symmetrical and Asymmetrical Figures Video Lecture | Mathematics for Grade 6

symmetrical and non symmetrical shapes
as we learned before we call a shape
symmetrical if we can draw a line that
divides it into two identical halves
this line is called the line of symmetry
we can fold the resulting two halves
across the line of symmetry to check if
they are identical here are some
geometrical shapes and real-life
examples let's see together if they are
symmetrical or not and count the lines
of symmetry for the symmetrical ones
this butterfly is symmetrical and as you
can see it has only one line of symmetry
which is a vertical line of symmetry
this image of the letter X is also
symmetrical it has a horizontal and a
vertical line of symmetry can you see
other lines of symmetry if you look
carefully you will find another two
lines of symmetry and they are diagonal
ones what about this geometrical shape
as you learned before it's called a
parallelogram and it has two pairs of
parallel lines but is it symmetrical
let's check it out obviously we can't
have a vertical line of symmetry for
this parallelogram the same thing goes
for the horizontal line perhaps a
diagonal line of symmetry could exist
well if we try this line we will get
these two parts which might look a bit
similar but they are not identical what
if we draw another diagonal line like
this we still have two different parts
therefore this parallelogram is not
symmetrical because it has no lines of
symmetry what about this shape it may
not be familiar to us but it is indeed a
polygon what do you think is it
symmetrical or not well obviously it
doesn't have a vertical or a horizontal
line of symmetry
our best choice should be this diagonal
line of symmetry if we try this diagonal
line the two resulting parts are
identical which means that this polygon
is symmetrical as you can see this
trapezoid has one line of symmetry
while this one is not symmetrical as you
can see
in this lesson you learned how to
distinguish symmetrical and non
symmetrical shapes and find the number
of lines of symmetry