Answer :
The length of a rectangle is found to be 18 cm.
An enclosed 2-D shape plane called a rectangle has four sides, four corners, and four right angles (90°). It has equal and parallel opposite sides. Because a rectangle is a two-dimensional form, it has length and width as its two dimensions. The length of a rectangle is considered as its longer side; its breadth is considered as its shorter side.
The perimeter of the rectangle is given as 54 cm. Let's consider the length of the rectangle as x and the width as y.
The formula to calculate the perimeter is 2(x+y).
The length is given as 2y.
Then, the perimeter is,
[tex]\begin{aligned}\text{Perimeter}&=2(2y+y)\\&=4y+2y\\&=6y\\54&=6y\\y&=\frac{54}{6}\\&=9\end{aligned}[/tex]
Then, the length is 2y=2×9=18.
The answer is 18 cm. Therefore, the correct option is option a.
To know more about rectangles:
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