Answer:
The length of rectangle is 3x.
Explanation:
Given that the perimeter of rectangle formula is P = 2l + 2w where l represents length and w is width. Then you have to substitute the expressions into the formula :
![p = 2l + 2w](https://img.qammunity.org/2021/formulas/mathematics/middle-school/o54261uhj4rxqb5lhjzl1skriu0c0us9ai.png)
Let p = 8x - 2,
Let w = x - 1,
![8x - 2 = 2l + 2(x - 1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rgmcubkugcgbv4x7gcqw71ebdfitu696xs.png)
![8x - 2 = 2l + 2x - 2](https://img.qammunity.org/2021/formulas/mathematics/middle-school/hv4irt93k1ws52lhijheerxvmr9xf8nbms.png)
Next you have to find the expression for length by moving all the unrelated terms to the other side :
![8x - 2 - 2x + 2 = 2l](https://img.qammunity.org/2021/formulas/mathematics/middle-school/4kz7bueurculkoyq161gvjen8oy7mkvfvy.png)
![2l = 6x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/txz8ruwu3s7srklfime273w18s0966m3rv.png)
![l = 3x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/qbzlox2svvk8gdw7snu5d1t9j8ef30uo64.png)