Question 1174359
the left side is the cost to the owner doing it all at home, the $100 printer and the variable cost per page.
the right side is the cost to to the owner taking it to the store, the $0.25 is the variable cost per page.
When they are equal is the break even point for how many pages need to be printed to make the printer worthwhile.
that is 0.20p=100 or p=500 pages need to be printed to pay for the printer and ink.