Solve the system of linear equations by substitution 4x − 2y = 16, 2x + y = 5

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made. determine an equation to model his situation?

Having a hard time understanding this question (see attachment).

Using only odd number for numerators write two different subtraction problems that have a difference of 3/4