How to make an equation for a table

At the electronics store you have a coupon for 20% off up to 2 cds you buy for cds with the original cost of $10.99 each the sales tax is 5% what is the total cost of your purchase

Felix wrote several equations and determined that only one of the equations has no solution. which of these equations has no solution?

The poll report includes a table titled, “americans using cash now versus five years ago, by age.” the age intervals are not equal. why do you think the gallup organization chose the age intervals of 23–34, 35–54, and 55+ to display these results?