Answer:
The new perimeter will be 2 feet shorter.
Explanation:
You are subtracting 1 foot from the width, meaning you are subtracting 1 foot from each of 2 sides. If you do that, your new perimeter would be 16 feet.
Original width:
6×2=12
18-12=6
6÷2=3
The original width was 3 feet.
To find the new perimeter:
3-1=2
2×2=4
6×2=12
4+12=16
The new perimeter is 16 feet, 2 feet shorter than the original (18 feet).