Given the perimeter of a rectangle and either the length or width, find the unknown measurement using the appropriate formula. A 1 ft -wide rectangular table has a perimeter of 12ft. The lengthl

Given the perimeter of a rectangle and either the length or​ width, find the unknown measurement using the appropriate formula. A 1 ft ​-wide rectangular table has a perimeter of 12ft. The lengthlength of the rectangle is ?