Answer:
The length is 26 cm, and the width is 6 cm.
Explanation:
The width is unknown. Let w = width.
The length is 8 cm more than 3 times the width.
length = 3w + 8
The perimeter is 64 cm.
P = length + length + width + width
3w + 8 + 3w + 8 + w + w = 64
8w + 16 = 64
8w = 48
w = 6
The width is 6 cm.
length = 3w + 8 = 3(6) + 8 = 18 + 8 = 26
The length is 26 cm