Applications of Algebraic Expression - Math, Class 7 Video Lecture

hello and welcome to the next session of
algebraic expressions in today's session
will be discussing real life
applications of algebraic expression
that is what are the application way we
are required to study this algebraic
expression and how to derive an
algebraic expression for the real time
real life applications so before
studying any subject we always always
have the confusion way we are required
to study this subject so i will give you
an example why we are required to learn
about egypt expression let's take an
example that we have three friends yours
whose name is like Sita Amina and a poo
so they have some marbles Amina has
sadita has some marbles Amina has ten
more marbles than sarita and let's say
up who has three more marbles then wat
Sarita and Amina has so let us try and
frame the question for it first here we
are saying that cerita has some marbles
so let's take an example of cerita
cerita have some marbles let us denote
that some with a variable X now let's
take that Amina has ten more marbles
then cerita so we take about Amina ten
more marbles den cerita so Sarita had X
marbles and ten more marbles so this 10
more will become X reactant to it now
the next is up who says that he has
three more marbles then the number of
marbles Cerreta and amina together so
let's talk about a pool here Appu has
whatever cerita has
plus whatever amina has plus he has
three more marbles so three so let's
stay put what cerita has here what Amina
has and additionally he has three more
marbles so this gives us the light
thumbs can we add together to form 2x
they can be added in the numerical way
as what we say that this is like
something as one x 1 x x 1 x x this like
terms can be added together this like
terms are constant so they can be added
together as a simple addition and that
gives us that a PO has a marbles 2x plus
13 so this way we derived added
algebraic expression of how many marvels
of who had so this is one of the
real-time example or your life occation
of algebraic expression let me take you
to the next example next application for
the same let's say here that Ramu
father's present ages three times
removes it let's take an example of what
is Ramos is as Ramos age is not defined
or not given we will put a variable Y
over here that is Ramos age now what is
it fade is wrong with fathers present
ages 3 tanks removes it so let's put
removes father's age
it's three times from whose age so three
dot why is Ramos father's age and Ramos
grandfather age is thirteen years more
than the sum of Rama's age and almost
father's it so let's first put what is
Ramos grandfather so Ramos grandfather's
age this is thirteen years more so let's
first put here 13 years more then the
wrong moves age what is Rama's 8y and
Ramos father age together so he will put
here three why so let's now come to the
simplification of it the like terms are
here why what is the like term like
terminals which have the same algebraic
factor so this way and this way both of
the same as if tech factor so 13 will
come here as it is as they are same as
Diptic factor they can be added as free
with the constant one so here this will
give us 13 plus 3y so this is how we try
to find out Ramos grandfather's it's
this is one more example of an algebraic
expression which gives numbers
grandfather's a and now let me take you
to one more application for the same now
this in this they are pushing our case
study is in a garden there are roses
marigolds are planted in square plots
remember square plot know the length of
the square plot in which marigolds are
planted is three times greater than the
length of the square plot in which roses
are planted so let's take about first
rest in pk's about roses
let's say we did note that the length of
the plot where roses are planted is l
remember that this is a square plot now
the length of the plots where Mary world
is planted is 3 meters greater than the
length of the square plot in which roses
are plant so here for marigold the
length of the plot is three times larger
than the longer than the length of the
rose plant now here we are talking about
only length not the area so what is the
question how much bigger'n area is the
medical plot then the roast for now by
destination area is length in two
lengths we already are aware of it so
let's see if i want to find area of Rose
plot then it would be length into length
that is l square now if i want to find
the area of a marigold plot
then it would be length into length but
here the length is what L plus three
okay two white confusion I would like to
say this is the length or this L denotes
the length area so it what is the length
of rose plant it's l so here we put L
square what is the length of marigold
man it's l plus three so here we put L
plus three the whole square so now what
is the question question is still not
answered how much bigger in area is the
Marigold plot then the Rose clock so now
to find out the same we have to take the
difference difference of marigold plot
minus dat of a rose cloth so that
difference is whole square minus l
square ok to valuate it this was the l
square plus 2 into length into 3 plus 9
minus l square so this would give me 6 l
last night so I think this example gives
you a clear idea about how we take one
entity or variable which is length and
then try to find out and associated
entity area in terms of an algebraic
expression so this free example actually
give an explanation of how and where a
player algebraic expressions are used
and what are their how to perform an
algebraic expression for those
application thank you