Each pack of dvds costs w dollars. If there is a discount of x dollars on each pack How much do you have to pay to buy each pack?
We know that each pack of DVDs costs w dollars. Let's introduce a variable p which will stand for the price of one pack of DVDs with the discount.

We also know that there is a discount of x dollars on each pack. So, the final price of each pack is equal to the original price minus the discount:

p = w - x.

Now we can substitute the value of p into the original equation and solve it for w:

w = p + x.

As a result, we have

w = (w - x) + x = p + x.