Answer:
x = 3
Step-by-step explanation:
7x - 9 + 3x = 2x + 18 - x
10x - 9 = x + 18
10x - x = 18 + 9
9x = 27
x = 3
To find the original price before the increase, divide the new price by 1 + the percent of increase.
198 / 1.20 = 165
The original price was $165
Y = 2x/x-7
x = 2y/y-7
xy - 7x = 2y
-7x = 2y - xy
-7x = y(2-x)
y = -7x / 2-x
y = 7x / x-2
f-¹(x) = 7x / x-2
Well $ 4.50 for the 24 pack.$2.50 for the 4 for 10,12 pack and the last is $3.00.