For this case we have the following expression:

Applying distributive property to the terms within parentheses taking into account that:

We have:

We add similar terms taking into account that:
Equal signs are added and the same sign is placed.

Thus, an equivalent expression is:

Answer:

So an additional discount of 50% off the sale price would bringthe price to 35% (that is, 50% • 70%) of the original price. Thus, a $100item would cost $35 after both discounts. An 80% off sale means thatyou pay 100% – 80%, or 20% of the original cost of the item.