Answer:
Let width is y;
The length of a rectangle is three times its width
length = 3 x width
= 3y
If the perimeter of the rectangle is 80
perimeter of the rectangle = 80
2(length + width) =80
2(3y + y) =80
2(4y)= 80
8y = 80
y=80/8
y= 10
width = y= 10
length = 3y =30
Explanation: