The price of an item is reduced by 20% of its original price. a week later it is reduced by 30% of the reduced price. the cashier informs you that there has been a total reduction of 50%. is the cashier using percentages correctly? if not, what is the actual percent reduction from the original price?

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18