Answer:
dollars per t-shirt
Step-by-step explanation:
<em>Read the problem and write your equation while following along with it</em>
We have 8 t-shirts
Lets 8 t-shirts be represented by 8t
So for our equation we will place and 
<h3>Our equation:

</h3><h3 />
Now it says we have a coupon that subtracts 4 dollars from our total
<h3>Our equation:

</h3><h3 />
The final part to add to our equation says that our total before tax was 36 dollars
<h3>So here is our equation:

</h3><h3 />
<em>add </em>
<em> to both sides</em>

<em>Divide both sides by</em> 
dollars per t-shirt
-Side note, make sure to spell your question right. It was a tad bit confusing to read at the start.
-Brainliest please :)