1 yard = 3 foot. 1 Foot = 12 inches.
She has 2 yards, 3 inches which = 6 foot 3 inches.
She needs 5 foot 9 inches.
She has more than enough, and to work out how much she has left -
3 inches - 9 inches = -6 inches. -0.5 foot.
6 foot - 5 foot = 1 foot.
1 foot - 0.5 foot. = 0.5 foot. She has 0.5 foot left over