width = 13
length = 30
p=2l + 2w
86 = 2(2w+4) + 2w
86 = 4w + 8 + 2w
86= 6w + 8
78 = 6w
13 = w
86 = 2l + 2(13)
86 = 2l + 26
60 = 2l
30 = l
check your work.
l is 4 centimeters more than twice w
twice w = 26
plus 4 = 30
i hope you understand. ask questions if not