What are the given rates??
Make a proportion the sales tax is a percent of the total purchase and you just have to figure that out. 1,200/100=72/x solving this i get 6% sales tax using that. I find the rest by taking 6% of 2500 =150. And for part b make another proprtion x/100=108/6. And i get 1800 dollars
You get an answer to your question really quick,
...like now!
You can do addition and substraction operations with polynomials similarly as with simple real numbers.
First of all you have to open brackets and then you can add numbers (-7-4=-11). Then the result is following:
not sure your question?
comment then i can edit my answer XD