I give a lot of points pls help.

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.

What is the value of x when x + 7 = 21?

If i have 20$ and i gave 5$ away how much i got