SOLUTION: I have presented this problem in the past and have not gotten a clear understanding of what is the correct formula and steps to take to get the correct answer. Please Help!!! Th

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Question 302686: I have presented this problem in the past and have not gotten a clear understanding of what is the correct formula and steps to take to get the correct answer. Please Help!!!
Ther perimeter of a rectangle is 20 meters. If the length is increased by four times the width, the sum is 19 meters. What are the dimensions of the rectangle? What is its area?
Found 2 solutions by Fombitz, ankor@dixie-net.com:
Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website!
Let's put down some formula first.

.
.
.
Now let's use the information we have,
"The perimeter of a rectangle is 20 meters"

1.
"If the length is increased by four times the width, the sum is 19 meters"
2.
Now you have 2 equations with 2 unknowns.
Use eq. 1,

Now substitute into eq. 2,

Then from eq. 1,

Then from those two,

Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
The perimeter of a rectangle is 20 meters.
If the length is increased by four times the width, the sum is 19 meters.
What are the dimensions of the rectangle? What is its area?
:
Let L = the length of the rectangle
Let W = the width
:
Write an equation for each statement
"The perimeter of a rectangle is 20 meters."
2L + 2W = 20
We can simplify this divide by 2, results:
L + W = 10
W = (10-L); this form for substitution
:
"the length is increased by four times the width, the sum is 19 meters."
L + 4W = 19
Substitute W with (10-L)
L + 4(10-L) = 19
L + 40 - 4L = 19
L - 4L = 19 - 40
-3L = - 21
L =
L = +7m is the length
:
What are the dimensions of the rectangle?
find the width
W = 10 - L
W = 10 - 7
W = 3m
:
Dimensions: 7 by 3
:
What is its area? 7 * 3 = 21 sq/m
:
:
Check solutions by finding the perimeter with these dimensions
2(7) + 2(3) = 20