Answer: The length of the rectangle would be 20 inches and the width would be 14 inches.
Explanation:
If the length is 20, first, it’s 6 more than 14, and second it would add up to 40. If the width is 14, it’s 6 less than 20, and adds up to 28. If you add those two together, you’d get your total of 68 inches for the perimeter!