A) $2.30 more.
B) y=0.085x
C) A sample table is attached, listing the values for x, the process and the value for y.
ExplanationA) The amount of tax on a $12.99 book is given by 0.085(12.99)=1.10415≈$1.10.
The amount of tax on a $39.99 video game is given by 0.085(39.99)=3.39915≈$3.40.
This gives us a difference of 3.40-1.10 = $2.30.
B) Using x as the cost before tax and y for the amount of tax, we have the equation y=0.085x.
8.5% = 8.5/100 = 0.085. To find the amount of tax, we multiply this rate by the cost, which gives us the equation above.