Spamming my wrong answers help? with the hw??

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.

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Ineed to know the answer right now! !