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The length of a rectangular garden is 3 feetmore than four times the width. Theperimeter of the garden is 66 feet. What isthe sum of the dimensions?

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Dimensions of a rectangular garden

We are going to follow the step-by-step:

Step 1 - naming each unkown dimension

Step 2 - finding two equations

Step 3 - finding the width and length

Step 4 - sum of the dimensions

Step 1 - naming each unkown dimension

We want to find the length and width of the rectangular garden. We are going to name both with a letter:

L: length

W: width

Step 2 - finding two equations

Based on the given information, we find a mathematical expression.

First equation

The length of a rectangular garden is 3 feet more than four times the width. This is

L is 3 feet more than 4 times W.

4 times W = 4W

If L is 3 feet more than 4W, then

L = 4W + 3

Second equation

The perimeter of the garden is 66 feet.

We know that the perimeter of a rectangle is the sum of all its sides:

length + width + length + width = 2length + 2 width = 2L + 2W

Then,

2L + 2W = 66

Step 3 - finding the width and length

Now, we want to solve the equations we found:

L = 4W + 3

2L + 2W = 66

we are going to do it using Substitution.

Finding the width

We substitute

L = 4W + 3

on the second equation:

2L + 2W = 66

↓ replacing L by 4W + 3

2(4W + 3) + 2W = 66

Now we have an equation with just one varible, so we can find W:

2(4W + 3) + 2W = 66

↓ distributive property 2(4W + 3) = 8W + 6

8W + 6 + 2W = 66

↓ since 8W + 2W = 10W

10W + 6 = 66

↓ taking 6 to the right side

10W = 66 - 6

↓ since 66 - 6 = 60

10W = 60

↓ taking 14 to the right side

W = 60/10

W = 6

Finding the length

Now we replace in any of the equations to find L (it will always be the same result). We use the frist equation we find:

L = 4W + 3

↓ replacing W by 6

L = 4 · 6 + 3

↓ since 4 · 6 + 3 = 27

L = 27

Step 4 - sum of the dimensions

We have that

W = 6 and L = 27, then their sum is

W + L = 6 + 27 = 33

Answer- D. 33

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