-3 (1/-3)=1
What property is this?^

What's the difference between: x≥0 and nonnegative integer. ?

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.