Question

Which expression represents the perimeter of the rectangle?

$(3x-3)(3x-1)$

• A. $6x+2$
• B. $12x-8$
• C. $6x-4$
• D. $12x+2$

Answer 1

The correct option is B

$12x-8$

Determine the perimeter of the rectangle.

The explanation for the correct options:

For option (B): $12x-8$

$$\begin{gathered} \mathrm{l}=(3\mathrm{x}-3) \\ \mathrm{w}=(3\mathrm{x}-1) \end{gathered}$$

Put the length and width value into the formula of the perimeter of the rectangle and calculate its value:

$\begin{array}{rcl}\mathrm{P}& =& 2(\mathrm{l}+\mathrm{w})\\ & =& 2\left(\right(3\mathrm{x}-3)+(3\mathrm{x}-1\left)\right)\\ & =& 2(3\mathrm{x}-3+3\mathrm{x}-1)\\ & =& 2(6\mathrm{x}-4)\\ & =& 12\mathrm{x}-8\end{array}$

Hence, Option B is the correct option.