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A rectangle with one side that is double the length of the other side can be seen as two squares beside each other, that are half the area of the original rectangle, in this case 18 square inches / 2 = 9 square inches.

The side of a square is the square root of the area, in this case the square root of 9 square inches, which is 3 inches.

Now think about the rectangle again. What we just counted was the side of a square that made up one half of the rectangle you wanted to calculate the area of. So the shorter side of the rectangle is the same as our square, and the longer side is double the length.

So the width of the rectangle is 3 inches, and the length is 2 * 3 inches = 6 inches.

Or:

Area = length x width (A=lw)

Area = 18 (in2)

Width = w

Length = twice width (2w)

18 = (2w)w

18 = 2w2

9 = w2

3 = w

The width is 3 in., the length (2w) is 6 in.

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Q: If the area of a rectangle is 18 square inches and the length of the rectangle is twice it's width what is the length and width of the rectangle?

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Do-it-in-your-head method: Length + width is half the perimeter which is 27 inches; 27 minus 6 is 21 and one-third of 21 is 7 which is the width. (Length = 2 x 7 + 6 = 20)

The rectangle is 12 units by 3 units.

Let L be the length of the rectangle and W the width, then L = 2W - 3. The perimeter = 2L + 2W = 2(2W - 3) + 2W = 6W - 6 But the perimeter measures 18"so, 6W - 6 = 18 : 6W = 24 : W = 4 The width of the rectangle is 4".

Assuming it is rectangle, then the perimeter equal twice the summation of length and width. Answer = 2 x (14 + 24) = 2 x 38 = 76 inches

Let the width = X. The length is twice the width plus 5. So the length must be 2X + 5. Area = 63 ft squared = X multiplied by 2X + 5 = 2X squared + 25. 2X squared = 63 - 25 = 38 2X = square root of 38. Therefore the width is the square root of 38 divided by 2 and the length is the square root of 38 plus 5.

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A rectangle has two dimensions, length and width. You haven't said what the width is. The perimeter is the distance around the rectangle. Imagine going round it. You would go 42 inches, then a width, then another 42 inches, then another width. In general, the perimeter of a rectangle is twice its length plus twice its width.

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The question is not quite clear in what's it's asking. Presumably it's asking what is the length and width of the rectangle? Let the length be 2x and the width be x: 2x*x = 18 2x2 = 18 Divide both sides by 2: x2 = 9 Square root both sides: x = 3 Therefore: length = 6 inches and width = 3 inches If it is asking what the width is, and the length is twice the area, then the width would be .5 inches. (L= A*2, L=36) (36*.5=18) (L*W=A)

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W=12,l=9 ((9*2)-6=12, 12*9=108)

2 (x + 2x) = 42 x + 2x = 21 3x = 21 Therefore, x = 7 The width of the rectangle is 7 inches. The length of the rectangle is 14 inches.

The length of a rectangle is twice its width. If the perimeter of the rectangle is , find its area.

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