Answer:
10
Explanation:
The perimeter will also be halved: (1/2)(20) = 10.
Example: a rectangle of length 14 ft and width 8 ft has perimeter P = 2(14 ft) + 2(8 ft), or 28 ft + 16 ft = 44 ft.
If we halve the length and width, we get 7 ft and 4 ft, and the P is
2(7 ft) + 2(4 ft) = 14 ft + 8 ft = 22 ft, which is half of the original perimeter 44.