Quadrilateral - An introduction, Math, Class 9 Video Lecture

hello those still welcome welcome to
this presentation from rising borough
I'm happy ho stuck with us Rory friends
today we are going to start a brand new
series series 8 called quadrilaterals
asked us for him seeking it give what do
we mean by quadrilateral or the say yeah
a Jamari webisode one of our brand new
CD c-- news 8 now those though hamachi
Carter happen a CD six or CD seven you
have gone through it series six maybe
talked about lines and angles and series
seven mayhem no but we had triangle ski
now though so the reason why it is
important is that at the cover those two
as we continue to learn advanced series
that is quadrilaterals parallelograms
etcetera etcetera up therefore because
that we are going to use a lot of things
that we have previously not so that's
neither up co-op attacks I mean he
really had to take a look at series six
and CD 7 we strongly recommend that
whenever you get a chance up a quote you
have to quickly take a look at those so
all of that said though such a lay let
us get started
Monte brand-new CD series eight
quadrilaterals knock of the hot box
father chilly those are submitters find
out what do we mean by quadrilateral let
us say come come to him on digitally
hung up Gordo pointed to him the plane
any two points so you're happy those
that you have one pair of two points you
have got 400 points under be here
similarly you have those that you have
got two more points you happy second
pair of two more points
so those up you have a what can you do
with these two points Kamala Meadows
though I'm gonna do here I married your
series may have we talked about Euclid's
geometry so hot oh no no Karthik II like
Jeff coffee octopus dough points would
be here you can always draw a straight
line connecting the two points so I
massacre K we can draw a straight line
similarly half of those that we can draw
a straight line in this fashion between
two points right naturally those so let
us take some more examples of you know
two points and how we can draw straight
lines so you happy up taking of those
code each of these cases when we have
got two points here two points here two
points here two points here so on so
forth and having two points for those
that we can actually draw a straight
line so other how may play in may if we
have any two points given have a maluma
we can
always draw a straight line so now those
two serve a lyric other manly judoka Joe
got an ergonomic 14 points that they
hang in the plane randomly tab up on T
no points will decay occurs at their
home so Chelios let us find out now
teen points of those thumb up to date
ahem now there can be two conditions
a Cossack t hockey all the team points
to him now put the e here they can be
collinear Collini r points so cool in
here come back let me heard whisker kim
and lee jae seok got America's teen
points so how make se we can draw a
straight line that actually passes
through each of these three points but
let me hug on all the three points you
see here my first point e his second
point in here third point after all
these points those curves they lie on
the same line
after all these points they lie on the
same line
I'm Cathy and these three points are
collinear but those they call I see a
quad condition as he who said bigger
Cuttino points to him they can be non
collinear they can be non collinear
right so in this case of some now put
the hung up of the hiya happy he have
three points or eighteen point I say
those so that they are not in a straight
line but up what you can do is so you
can draw a straight line between any two
points right so in da no coin can be
chopping straight line proper set or
something like this similarly in the low
points can be chopping straight line
rocker sector security and finally
between these two points you can draw a
straight line some you think ago so grab
a say Kirk eighteen t non collinear
points gonna say what you can do is
actually you can draw a triangle how can
the hero stuff from our last series job
that is series seven we talked about
triangles have never happy they hear a
lot about triangles triangles kiss a
getting a congruent triangles different
rules for triangles etcetera etcetera so
those still home detective occupies Doe
points with he hit about straight line
rockers that we ho octopus at the team
point who the head throw our teen point
collinear head to octopus you can draw a
straight line either after pass teen
point non collinear and that is these
points do not lie on the straight line
then you can actually make a triangle
out of this right
so this are now managed at this time are
there hammock secure to him
it comes and goes before we ask you for
points let us take some more examples of
collinear and non collinear three points
so you have it goes to ham neck for the
higher key here you have three points
which are collinear you can draw a line
like this yeah but those similarly you
can have three points and you can draw a
straight line like this or two so these
are three examples you have occupies the
non collinear points here in each of
these one two and three or own Tina non
collinear points with the stock it up
joint cut the hood then you get
triangles so now those that we are going
to talk about IV though points and thin
points again Hannity j'tia plane maybe
we have taken a look at it what about
now if we have four points now this
actually let us find out now Jeff
Americas was a child pointer t if you
have any four points in the plane I got
America's Co which are pointer in the
plane so cuz they I see ho saktha hai ki
chart points can be actually cool in
here again right Butler baccarat Chara
point if they can lie if they lie on the
same straight line then you can draw a
straight line passing through four
points and in this cases to all the four
points are collinear
now the sake of Jesus he was happy here
he managed a team point he collinear
three points are collinear
Jojo three point two that is non
collinear so in this case those though
you have you have a one : 8.2 collinear
point and three : air point yet in a
collinear point and you have a non
collinear point so this is the only non
collinear point however se-ho do so so
we can again draw a triangle out of this
right now this walkway combination
possible heck yeah chart points key
eight - HRO point straight line may
happy or requires 18 point straight line
man but it caught your three point you
happy so yes there are there are a
couple of more ways that you can have
four points in a plane today let us take
a look at them how about if you have
four points like this so you have to
first point second point third point and
fourth point you have to update the hair
those the charter points Koli
right because you can always draw a
straight line between any two points
like in EHR a point a second could be a
high key they do not fall on a straight
line right and also T no point three
straight line manner here so those were
when you have and those are so similarly
update okay this is one figure and this
is another figure soja happy you have
four points and EHR of which other
points they are not collinear
so now goes to what we are realizing is
that Jeff a massacre K in a drawing Java
- like a drawing cut the hedge of um
joined cutting a straight lines go in
order
so those that we get a closed figure
like this so you can shape a I'm a
volume a triangle triangle beam angles
yeah fit
triangles they have three angles three
sides so what kind of shape is this you
have to go so we have one two three four
sides so clearly this is not a triangle
so this in a hunk at the head
quadrilateral you know hum cut the head
quadrilateral so this way a
quadrilateral is coming from two Latin
words so yeah here so quad raise a Latin
word just come MATLAB hey chow for or eh
it also held lateral this actually comes
from a word called lattice just come up
love hey sides so another so you can say
this is a no brainer charge sides so ik
s he closed figure jaha pay you have
four sides who set up getting a
quadrilateral now though so H is Johan
op save up cannot your hang it is that a
graph notice curvy in Doha Modesto
the there is one unique thing is
particularly quadrilateral middle so you
don't know hey quadrilateral here like
it is quadrilateral - buckle up is angle
cone otoscope a whole this angle is a
reflex angle this angle is a reflex
angle Q reflex angle head rose / UK
reflex angle Chile I said let us write
the whole thing angle reflex angle has
any angle which is actually greater than
180 degrees and less than 360 degrees
how many those are marriages cd6 did you
have to be talked about lines and angles
wha-bam the Det water reflex angles so
those though for this webisode and going
forward in this series
Jeff Cappy Humbert caring a
quadrilateral key we are going to always
talk about this type of quadrilateral
choppy each of these angles are actually
less than 180 degrees and the Siham we
are not going to talk about these kind
of quadrilaterals so this is something
that we just wanted to share with you
those though even though both are
quadrilaterals because quadrilateral
Kamaka does the koi be closed figure
that has four sides that is the
definition of quadrilateral but those
are for this presentation and all for
the rest of this series chapter v humbug
telling a quadrilateral key you should
remember that we are talking about this
kind of quadrilateral Shahab a each of
these angles are less than 180 degrees
so this all of that said naturally I
can't contain let us now learn a little
bit more about this new thing called
quadrilateral so the sum should work at
the heavy ache with a formal definition
key quadrilateral so a closed figure
formed by joining for non collinear
points in an order so he said I'm
captain have a sub quadrilateral system
at Libya who uh commander Jagger have a
Muhammad plane maybe have got four
points a B C and D again Hamada pass CHR
points immediately have plane me which I
am non collinear so hum Calcutta head
was the first we join a b then we join
bc i'm ordered by those that we are
going and joining all these points then
CD and finally goes to DA so a sega
cluster we join all the we join all the
points and then we get a close figure so
yes i'm a close figure military those
that is a ham cat the heck quadrilateral
right
Acosta's da Swapna notice
co-come triangles kibarim about that
they hit a so up near Acosta how
triangles Kobe represent them as
triangle ABC khaki right yes a triangle
PQR Kirk a mother Jotham licked ahem a
statement me so we represent them like
this so quadrilateral koto so we write
them as simply quadri lateral ii b c d
but the hamas kisame we don't do any
small figure or SEO drawing the heck out
there so we write the whole word
quadrilateral and then we write the name
ABCD jo b RK quadrilateral keen arm have
you have to write it like this so when
we say quadrilateral ABCD is also so
this means hum is quadrilateral chimera
me bat Callaghan now that we are going
to look at some of the other unique
points too so one thing goes that we
notice is that a jockey quadrilateral
Hadassah it has four corners or vertices
four corners or vertices you get your
corner suppose the a B C and D these are
four corners or four vertices second
cheese also notice contains there are
four signs well that is the reason why
they're called quadrilaterals right so
sides of it goes for a B this is your
first side BC CD and da f it ad so jump
tell me I'm getting us a quadrilateral
upper cuts amylum can me hang a
quadrilateral has four sides and those
are finally quadrilateral has four
angles so clearly up there we go so from
the figure you can see you have the
angle a you have the angle B yeah okay
angle C and you have the angle T so
those so these are the four angles up
angle a coke except we have BA D and
you'll be coke except they have C a B
angle C Co we can say B C D and angle D
Co we can say C D a so this is how
making like a quadrilateral Kasich at
the head a psychic a hum quadrilateral
form cut the hair how we write a
quadrilateral and the fact of the so
quadrilateral has four corners or four
vertices
and it has four sides a BBC CDDA and it
has four angles so those so next we are
going to talk about different types of
quadrilateral scheme so the sad case may
be submit when he I believe every
someone filming a protective shukriya
and never