I need help please on number 19

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.

Im literally having a mental breakdown

Ahyperbola centered at the origin has a vertex at (-6,0) and a focus at (10,0)