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Heron's Formula | Heron's Formula - Exercise 12.4

Question 4

A rectangular plot is given for constructing a house, having a measurement of 40 m long and 15 m in the front. According to the laws, a minimum of 3 m, wide space should be left in the front and back each and 2 m wide space on each of other sides. Find the largest area where house can be constructed.

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  • Solution

  • Transcript

Let the given rectangle be rectangle PQRS,

According to the question,

PQ = 40m and QR = 15m

As 3m is left in both front and back,

AB = PQ -3 -3

⇒ AB = 40 -6

⇒ AB = 34m

Also,

Given that 2m has to be left at both the sides,

BC = QR -2 – 2

⇒ BC = 15 -4

⇒ BC = 11m

Now, Area left for house construction is area of ABCD.

Hence,

Area(ABCD) = AB × CD

= 34 × 11

= 374 m²

"hello students welcome back on the nero down solving session and in today's video without solving session we are going to understand how to find out the area of rectangle all right so i will read the question first a rectangular plot is given for constructing a house having a measurement of 40 meter long and 15 meter in the front so length and breadth is given here okay length is uh 40 meter and with this 15 meter right so according to the long the minimum of three meters wide space should be left in the front and back so find the largest area where the house can be constructed all right and for that okay we have drawn this figure okay this is our plot pq ras right which is rectangular initial okay now let's solve this question so as we know that the given triangle is okay triangle sorry given rectangle is given rectangle is p q r s all right so in the pq areas the length of p3 is given here right the length of pq pq is equals to 40 centimeter and the length of okay qr is also given here so qr is equals to 15 centimeter all right now according to law okay uh three meters is left in both front and back directions right so that's why okay the length of eb will be okay a b will be p q minus 3 minus three right because okay we have to let three meters okay from the front and back as well right so which is equals to 40 minus three minus three right so a b will be 34 centimeter all right okay in the similar way okay we will find out the cd okay so we have given that the two meters has to left in okay both the sides right so the cd will be qr minus 2 in the front direction and minus 2 which is for back direction right which is equals to qr is 15 minus 2 minus 2 okay and that's why the cd will be 11 centimeter all right now okay basically uh okay we get the length for rectangle abcd as well as we get okay brit as well that is 11 centimeter all right so we have to construct the house okay for the flat that is it is a rectangular flat abcd all right so now what we will do we will find out the area of rectangle abcd right so area of rectangle area of rectangle [Music] abcd is equals to it is base into okay length integral right it is l into b okay so the length is 34 centimeter and break this 11 centimeter right so that's why okay 34 multiplied by 11 is equals to 374 meter square all right okay and that's why okay uh the area left for the house of construction is 374 meter square right so area for house construction construction okay will be 374 meter square all right so i hope you understood this if you have any doubt please leave your comment below and please do subscribe to this channel thanks for watching this video bye "

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Question 4

A rectangular plot is given for constructing a house, having a measurement of 40 m long and 15 m in the front. According to the laws, a minimum of 3 m, wide space should be left in the front and back each and 2 m wide space on each of other sides. Find the largest area where house can be constructed.

  • Solution

  • Transcript

Let the given rectangle be rectangle PQRS,

According to the question,

PQ = 40m and QR = 15m

As 3m is left in both front and back,

AB = PQ -3 -3

⇒ AB = 40 -6

⇒ AB = 34m

Also,

Given that 2m has to be left at both the sides,

BC = QR -2 – 2

⇒ BC = 15 -4

⇒ BC = 11m

Now, Area left for house construction is area of ABCD.

Hence,

Area(ABCD) = AB × CD

= 34 × 11

= 374 m²

"hello students welcome back on the nero down solving session and in today's video without solving session we are going to understand how to find out the area of rectangle all right so i will read the question first a rectangular plot is given for constructing a house having a measurement of 40 meter long and 15 meter in the front so length and breadth is given here okay length is uh 40 meter and with this 15 meter right so according to the long the minimum of three meters wide space should be left in the front and back so find the largest area where the house can be constructed all right and for that okay we have drawn this figure okay this is our plot pq ras right which is rectangular initial okay now let's solve this question so as we know that the given triangle is okay triangle sorry given rectangle is given rectangle is p q r s all right so in the pq areas the length of p3 is given here right the length of pq pq is equals to 40 centimeter and the length of okay qr is also given here so qr is equals to 15 centimeter all right now according to law okay uh three meters is left in both front and back directions right so that's why okay the length of eb will be okay a b will be p q minus 3 minus three right because okay we have to let three meters okay from the front and back as well right so which is equals to 40 minus three minus three right so a b will be 34 centimeter all right okay in the similar way okay we will find out the cd okay so we have given that the two meters has to left in okay both the sides right so the cd will be qr minus 2 in the front direction and minus 2 which is for back direction right which is equals to qr is 15 minus 2 minus 2 okay and that's why the cd will be 11 centimeter all right now okay basically uh okay we get the length for rectangle abcd as well as we get okay brit as well that is 11 centimeter all right so we have to construct the house okay for the flat that is it is a rectangular flat abcd all right so now what we will do we will find out the area of rectangle abcd right so area of rectangle area of rectangle [Music] abcd is equals to it is base into okay length integral right it is l into b okay so the length is 34 centimeter and break this 11 centimeter right so that's why okay 34 multiplied by 11 is equals to 374 meter square all right okay and that's why okay uh the area left for the house of construction is 374 meter square right so area for house construction construction okay will be 374 meter square all right so i hope you understood this if you have any doubt please leave your comment below and please do subscribe to this channel thanks for watching this video bye "

Our top 5% students will be awarded a special scholarship to Lido.

subject-cta
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