Why the absolute value of a number is never negative

You put the following items into your rucksack. ham 600 g cheese 380 g tomatoes 270 g how much do all the ingredients weigh in total?

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?

Rectangle pqrs has length a and width 4b. the x-axis bisects ps and qr what are the coordinates of the vertices