Jay can buy a stereo either online or at the local store. if he buys online he gets a 15% discount, but has to pay a $12 shipping fee. at the local store, the stereo is not on sale, but there is no shipping fee. for what regular price is it cheaper for jay to buy the stereo online

When the price of the stereo is more than $80, then it will be cheaper to buy the stereo online.

Step-by-step explanation:

Lets us assume that the price of the stereo is x.

If Jay buys online he gets a 15% discount, but has to pay a $12 shipping fee.

=>

So, x = 80

And 15% of 80 is :

dollars

Jay saves $12 but he has to spend $12 in shipping.

Up to $80, it does matter whether Jay buys the stereo online or at the store.  

But when the price of the stereo is more than $80, then it will be cheaper to buy the stereo online.

sup

step-by-step explanation:

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80