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Geometry

a rectangular garden bed was built against an exisiting brick wall. 24m of ediging was used to encolse 60m^2. find the dimensions of the garden bed to the nearest cm.
Original post by Shreyarijal
a rectangular garden bed was built against an exisiting brick wall. 24m of ediging was used to encolse 60m^2. find the dimensions of the garden bed to the nearest cm.


drawing a diagram and setting up the equations for the perimeter and area are usually the way to go. Post what you try.
Original post by Shreyarijal
a rectangular garden bed was built against an exisiting brick wall. 24m of ediging was used to encolse 60m^2. find the dimensions of the garden bed to the nearest cm.


Let's model this properly.

Draw out the diagram.

Let the rectangle has 2 lengths: x and y (I like to be conventional)

As the garden is enclosed against a brick wall, either dimension x or y are deducted from the menasure of the perimeter (I don't know which of the 2 you used in your diagram, but I will label this length x)

Edging = 24m = x + y + y (or x +2y)
Area = 60m^2 = xy

(Full solution edited out)

Use the substitution method to solve the simultaneous equations.
Reply 3
As area = length x breadth, 2b + l = 24 and. b x l = 60. Solve these by substitution and don’t forget to convert dimensions in to cm
Original post by Shreyarijal
a rectangular garden bed was built against an exisiting brick wall. 24m of ediging was used to encolse 60m^2. find the dimensions of the garden bed to the nearest cm.


You have an area of 60 m^2 (A) and you already know that 24 m is your perimeter (P). That can be done in the equations of your formulas.

A = x * y
P = x + 2y (just one x, because the side of the brick wall has not to be fenced).

Let x and y be the length and width of your rectangular and you are able to calculate the missing unit.

Spoiler

(edited 1 year ago)
Original post by Zarek
As area = length x breadth, 2b + l = 24 and. b x l = 60. Solve these by substitution and don’t forget to convert dimensions in to cm


Original post by MindMax2000
Let's model this properly.

Draw out the diagram.

Let the rectangle has 2 lengths: x and y (I like to be conventional)

As the garden is enclosed against a brick wall, either dimension x or y are deducted from the menasure of the perimeter (I don't know which of the 2 you used in your diagram, but I will label this length x)

Edging = 24m = x + y + y (or x +2y)
Area = 60m^2 = xy

24 = x +2y
60 = xy

Use the substitution method to solve the simultaneous equations.


Guys, it is too kind of you two to show the solution process here. But instead of telling the single steps, just give some clues what has to be done. This forum has a special rule and it is not allowed to explain the whole steps to the answer.

Otherwise @Muttley79 appears and bite you! :yes:
(edited 1 year ago)
Original post by Kallisto
Guys, it is too kind of you two to show the solution process here. But instead of telling the single steps, just give some clues what has to be done. This forum has a special rule and it is not allowed to explain the whole steos to the answer.

Otherwise @Muttley79 appears and bite you! :yes:

I do - and I try to avoid quoting the whole of the rule breaking post :smile:

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