The perimeter \( P \) of a rectangle can be calculated using the formula:
\[ P = 2(L + W) \]
where \( L \) is the length and \( W \) is the width. Given that the perimeter is 84 meters and the length is 35 meters, we can set up the equation:
\[ 84 = 2(35 + W) \]
Now, divide both sides of the equation by 2:
\[ 42 = 35 + W \]
Next, solve for \( W \) by subtracting 35 from both sides:
\[ W = 42 - 35 \] \[ W = 7 \]
Thus, the width of the rectangle is \( 7 \) meters.
The correct answer is \( w = 7 \) meters.