Betty's Department Store is having a clearance sale. Everything in the store is off. The items Xander bought have a pre-sale total price of y dollars before sales tax. Part A: Write two equivalent expressions that represent the total cost of the items at sale price before tax in terms of y, and explain how the two expressions relate to one another. Part B: Which expression is more useful? Why?

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.