Examples (NCERT): Miscellaneous Video Lecture | Mathematics for Airmen Group X - Airforce X Y / Indian Navy SSR

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1 - part 11
the potion says a line for pentothal
line segment joining points 1 0 and 2
comma 3 divides it in ratio 1 by n find
the equation of the line let's draw a
line first so let's suppose this is 1
comma 0 and this is too common field
this is mine pinky
now the question see is align / pending
through the line segment so this line
perpendicular to this and this divides
the line in ratio 1 is to N and this is
perpendicular also and we have to find
the equation of line L this is the first
line help now we need at least one point
and slope of line head to find the
equation this point we can find let's
suppose this the point is yes since this
point this point this is divided member
they show one is 2n they can find out
yes although since we can find the slope
of line PQ you can also find this off of
L because DQ is perpendicular to them so
first find slow-walking
l and the point s so let's find the
point s first so s will be since it is
divided into 1 ratio 2 into 1 2 into 1
plus 1 into n it is n by 1 plus this is
x over in comma 3 into 1 that is 3 plus
0 n that is 0 by 1 plus this is the
value of point X no slope of T Q is M of
P Q is equal to y2 minus y1 that is 3
minus 0 by 2
3 minus 0 by 2 minus 1 that terms so
slope of line ml is nothing but minus 1
by because ml into VQ should be equal to
minus 1 if you multiply these two you
will get minus 1 so we have point and we
have so muscles we have point here so we
can find the equation the equation is y
minus then take one point that is this
point 3 by 1 plus n is equal to M M is
equal to minus 1 by 3 into X minus X
naught X notice 2 plus n by 1 plus so
what we have used here we have use this
formula y minus my naught is equal to M
into X minus X now this formula we have
used so we have the value of y naught
this is why not we have the value of M
this is them and we have the value of x
own that is now let's solve this but
tell now what we have done is it just
drawn the diagram and then we we knew
that we should have slope M and wish to
have the point s we got this point we
got the stone and now we are going
differently English so what we get here
is C will put like this here what we get
is 3 into y into 1 plus M minus 3 by 1
plus in class
X into 1 plus n minus 2 plus n by 1 plus
n 1 correct now since it is 0 we can
remove this part out so this is 0 this
becomes 3 into y plus NY minus 3 plus X
plus XM minus 2 minus n is equal to or
let's take the X bar first so we get X
squares X here we get X here X X plus xn
0 X bar plus 3 into y plus 3 y n is y
part so we have taken X bar we have
taken by part now the part remaining is
this is minus 9 we have taken this part
this is minus 2
you have taken this part and this is
minus N is equal to Z what we can say is
X this becomes X into 1 plus n plus 3 y
will they come into 1 plus n is equal to
11 plus or we can take X plus three Y
into 1 plus n is equal to 11 plus n or
write this equation here or we get X
plus 3y is equal to 11 plus n by 1 plus
this is the equation this is the
equation we have very simple what we
have done we have found the slope and we
have found one point then we have a
user's equation y minus y not expect
into X minus X naught and yes we spent
two novels always equations very simple
it looks lengthy but it's very simple
equation the owner of a mill stored
finds that he can sell 9f litres of milk
each week at 14 degrees for it and one
to lose the litters of me each week at
16 degrees per litter as you mean the
linear relationship between selling
price and the demand
how many litters can he sell weekly ad
70 rupees per litter
so let's assume this is a line so he is
telling that when he is seeing what in
interpreting it was Ruby spotting per
liter he is selling 980 let us when is
charging 16 liters to 60 degrees per
liter he is selling 1 to 2 0 users when
he's charging 70 liters he is selling
white Wilder some girls need to find the
value of 5 because the linear
relationship is maintained please note
this linear relationship is is a
critical point here since in linear I
can draw a line when he was selling for
10 rupees per liter he sold my
additional many as he was selling at 16
is per liter he sold one two two zero
later something
now the portion is when he is selling
for 17 is pollutant how much or how many
litres of milk he will say for this line
is find the slope Slom is nothing but Y
2 minus y el by X 2 minus so this is 1 2
to 0 by 9 80 by 60 minus 40 that is 245
that is 120 this is the slope now since
this is 1 the slope will hold true for
all this so now as we if we can take
this point and we want to find the slope
we can do like this we say y -1 2 to 0
by 17 minus 16 is 31
so now we have to gain these two pilot
suppose this two points are PQR earlier
we took you Anna
this is 40 why not nah we'll take P Q so
for P Q the slope will be y -1 2 to 0 by
17-16 and this will also be 120
so whatever it be it is y -1 to 0 is
equal to 120 into one because 70 minus 6
is 21 or Y is equal to 1 to 2 0 plus 120
that is nothing but 1 3 4 0
laterz and that decides it isn't it we
have this line we have 3 points and
almost all the points are given we have
to find the Y a little thank you visit
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