Width of a Rectangle with Given Perimeter

A rectangle has a length that is 4 units longer than its width. If the perimeter of the rectangle is 56 units, what is the width of the rectangle? Let the width be represented by $x$. Write the dimensions in terms of $x$ and use the perimeter formula, $P = 2L + 2W$. Find the value of $x$ and provide your answer in the grid format as a decimal.