We first add the tax to the non-food items. We have ($3.00+$.50)*1.05=($3.50)*1.05=$3.675 (Which can be rounded up to $3.68, since we can't have a fraction of a cent).
Now, we add the cost of the food to $3.68. As a result, we have $3.68+$2.50=$6.18 as the total bill.
You may have have forgotten to find the measure of A. Which would by using your 6 that you got would be 19.
16X-6=90
96=16X
X=6
8X6-29
48-29
19
