Answer:
w = 5
Explanation:
The perimeter of a rectangle is given by
P = 2(l+w)
28 = 2(2w-1 + w)
Combine like terms
28 =2(3w-1)
Divide each side by 2
28/2 = 2/2(3w-1)
14 = 3w-1
Add 1 to each side
14+1 = 3w-1+1
15 = 3w
Divide each side by 3
15/3 =3w/3
5 =w