Here is the information we have:
1. The perimeter is at most 130 cm.
2. The length of the rectangle is 4 times the width.
We can let l stand for length and w for width.
The formula for the perimeter of a rectangle is 2l + 2w.
We have to change the formula a bit.
The length of this rectangle is going to be 4 times the width
So, replace 2l with 2(4w).
Then make this equation equal to 130.
2(4w) + 2w = 130 ; Start
8w + 2w = 130 ; Distribute the 2 across the 4w
10w = 130 ; Combine the like terms 8w and 2w
w = 13 ; Divide both sides by the coefficient of w. Which is 10
