:an item has a price tag of $35 and another tag that says, "20% off." what is the sale price?

So 20 percent of 35 is 7.

Look at it this way:
20%
20*5=100

35 divided by 5 is 7.

So the sale price we would take7 from 35 to get 28.00 which is your answer.

Ps don't do it the way i did because i already knew the answer,and the way i worked it out worked this one time but there are no gaurentees for the next.

You must be wondering why we subtracted that 7 from 35 and why 7 isn't the full answer. Well, 7 was the factor, basically every 20 percent you would subtract 7. So if it were 40% off it would be 14. Or 60 percent would be 21. You subtract that number from the original price to get the sale which in this case is 28.00

Your 28.00

Hope this helped!:)