Answer:
What do not you understand?
Answer:

Step-by-step explanation:
Given
The attached triangle
Required
Find y
The attached triangle is isosceles; so:

Also, we have:
--- angles in a triangle
Substitute: 

Collect like terms


N-2.5 represents the cost for each shirt being subtracted by $2.50 due to the coupon
Answer:
33
Step-by-step explanation:
10+23 according to my sense