The basic way to calculate a discount is to multiply the original price by the decimal form of the percentage. To calculate the sale price of an item, subtract the discount from the original price. You can do this using a calculator, or you can round the price and estimate the discount in your head.
Is there answer options because if not then it would possibly be y = 45x + 540 or it could be 45x = 540 or it could be 45x/540 so it can be any of those :)
