What's the answer to the question "a number is k units to the left of 0 on the number line. describe the location of its opposite."?

The opposite of a number k units to the RIGHT of 0 the "origin" on a number line would have to be a number k units to the LEFT of 0 the "origin" on a number line.
Basically, it would be a negative number instead of a positive number, but the absolutely value of both values of k would be the same. It's just the placement of the new number will be negative.

   K units to the right of 0 on the number line

11123355543321112345566444

No he does not because he can only cover 12 square feet from 15 square feet which he will still need 3 more. this is because if 3×5=15 square feet and 15-12=3 which thats the answer