Solve the following equation for yy -2x+9y=18

The answer is 7.2 how would you put this as money

The price of one share of a company’s stock declined $13.89 every day for 2.5 days what was the stocks total decline in price

Amotorboat maintained a constant speed of 12 miles per hour relative to the water in going 45 miles upstream and then returning. the total time for the trip was 8.0 hours. use this information to find the speed of the current.