P = Perimeter
L = Length
W = Width
L = 1 + 2W
W = W
Rectangle has 4 sides
2 ( 1 + 2W ) + 2W = 62
Distribute
2 + 4W + 2W = 62
Simply
2 + 6W = 62
Solve for W
6W = 60
W = 10
Plug 10 in for W in the Length formula to find Length
L = 1 + 2(10)
L = 1 + 20
L = 21
Check if wanted**
2(L) + 2(W) = 62
2(21) + 2(10) = 62
42 + 20 = 62
62 = 62
:D