l = 3 + 2w
2l + 2w = perimeter
66 = 2(3 + 2w) + 2w
2 * 3 = 6
2 * 2w = 4w
6 + 4w + 2w = 66
4w + 2w = 6w
6 + 6w = 66
-6
6w = 60
/6
w = 10
Width = 10
l = 3 + 2 * 10
2 * 10 = 20
20 + 3 = 23
23 = l
23 * 2 + 10 * 2
46 + 20 = 66
The largest possible length is 23cm.
The largest possible total length is 46cm.
