What is the value of x if 6x+7=13x-9

If the measure of xyz is 81 what is the measure of yz

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.

Xy x xy if a and b are positive integers such that a*b=9 and b*a=72 what is the value of a/b