Heather paid $1,493.30 for a computer. If the price paid includes a 9% sales tax, which of the following equations can be used to determine the price of the computer after tax?
(Let x represent the cost of the computer and y represent the total cost after tax.)
A. y = 1.09x
B. y = 0.91x
C. y = 1.9x
D. y = x + 9x