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The length of a rectangle is 7m less than twice the width. If the length is decreased by 1 m and the width is decreased by Am, the perimeter will be 66m. Find the dimensions of the original rectangle.

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Final answer:

To find the original dimensions of a rectangle given the length is twice the width minus 7 meters, and with changes in dimensions, the new perimeter is 66 meters; we use algebraic expressions and solve for the original width and length.

Step-by-step explanation:

Understanding Rectangle Dimensions

To solve for the original dimensions of the rectangle, let's let the width be represented by w and the length as L. According to the problem, the original length of the rectangle is 7m less than twice its width. This can be written as:

L = 2w - 7

After decreasing the length by 1m and the width by Am, the new dimensions become L - 1 for the length and w - A for the width. The problem then states that the perimeter is 66m, which can be expressed as:

2(L - 1) + 2(w - A) = 66

Now we can substitute the expression for L into the perimeter equation:

2((2w - 7) - 1) + 2(w - A) = 66

Simplifying, we get:

4w - 16 + 2w - 2A = 66

And further simplifying:

6w - 2A = 82

However, we are not given the value of A, we might assume A is a typo and should also be 1. This would yield:

6w - 2 = 82

Solving for w gives:

w = 14 m

Substituting back into the length equation:

L = 2(14) - 7 = 21 m

Therefore, the original dimensions of the rectangle are 14 meters in width and 21 meters in length.

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