## anonymous one year ago .

1. anonymous

Let P(y) represent the final cost of the DVD,

2. anonymous

If you have a discount of 12% off, that is $y \times (1-0.12)$. Correct?

3. anonymous

12% off means that you pay only 88% of the original cost.

4. anonymous

Now, let's write the tax added cost. 3% tax means: $y \times (1 + 0.03)$

5. anonymous

The expression means that you need to pay an additional 3% on top of your original cost.

6. anonymous

Let's combine the expressions together.

7. anonymous

okay

8. anonymous

$P(y) = (y \times (1-0.12)) \times (1+0.03) = y \times 0.88 \times 1.03$

9. anonymous

First of all, you cannot subtract 0.03y. You are paying tax, not getting a discount.

10. anonymous

*messed

11. anonymous

You can subtract the 0.12y as that is your discount.

12. anonymous

Yes, your signs are mixed up.