Working With A Rectangular Garden

  • #1
nycmathguy
Homework Statement
1. Draw a diagram representing the problem.
2. Write equation representing the perimeter.
Relevant Equations
P = 2L + 2W
The length and width of a rectangular garden are 15 meters and 10 meters, respectively. A walkway of width x surrounds the garden.

(a) Draw a diagram that gives a visual representation of the problem.

(b) Write the equation for the perimeter y of the walkway in terms of x.

For (a), see attachment.

For (b):

y = 2L + 2W

y = 2(x + 15) + 2(x + 10)

y = 2x + 30 + 2x + 20

y = 4x + 50

Is any of this right?
 

Attachments

  • Screenshot_20210619-182339_Drawing Pad.jpg
    Screenshot_20210619-182339_Drawing Pad.jpg
    18.1 KB · Views: 141
Physics news on Phys.org
  • #2
nycmathguy said:
Homework Statement:: 1. Draw a diagram representing the problem.
2. Write equation representing the perimeter.
Relevant Equations:: P = 2L + 2W

y = 2(x + 15) + 2(x + 10)
y=2(2x+15)+2(2x+10)
 

Attachments

  • garden walkway width x.jpg
    garden walkway width x.jpg
    11.4 KB · Views: 153
  • Like
Likes nycmathguy
  • #3
anuttarasammyak said:
y=2(2x+15)+2(2x+10)
I was right the first time but doubted my work.
 
  • #4
nycmathguy said:
A walkway of width x surrounds the garden.
(a) Draw a diagram that gives a visual representation of the problem.

nycmathguy said:
I was right the first time but doubted my work.
Your diagram, which is part a, is incorrect. The work for part b, but it doesn't align with your drawing. You have x being the length of the short side of the outer rectangle. Per the problem statement, x is the width of the walkway.
 
  • #5
I think we should discriminate between the outer and the inner perimeter of the walkway.
The outer perimeter of the walkway is 2(2x+15)+2(2x+10).
The inner perimeter of the walkway is equal to the perimeter of the garden, that is 2*15+2*10.
 
  • Like
Likes SammyS and Mark44
  • #6
Mark44 said:
Your diagram, which is part a, is incorrect. The work for part b, but it doesn't align with your drawing. You have x being the length of the short side of the outer rectangle. Per the problem statement, x is the width of the walkway.
Can you draw the right figure for me?
 
  • #7
nycmathguy said:
Can you draw the right figure for me?
Come on... you can do it. The garden is 15 by 10, and there is a walkway around the garden that is x feet wide.
 
  • #8
Mark44 said:
Come on... you can do it. The garden is 15 by 10, and there is a walkway around the garden that is x feet wide.
See attachment.
 

Attachments

  • Screenshot_20210621-164120_Drawing Pad.jpg
    Screenshot_20210621-164120_Drawing Pad.jpg
    20.4 KB · Views: 127
Back
Top