Answer:
Qu. 8 = A (50) = 25w as 125w x 125l = Area ; this because perimeter 500ft would always be a 3:5 ratio to the larger area. Therefore perimeter is 125+125 +125 +125 and = 500ft. However we can prove if 125 is any length or width then A(50)= 1/5 = 25 Qu 9)= I think last 2 are a function. Qu 10) Answer B is correct.
Step-by-step explanation:

Multiply 50 by 0.90 because you take a discount of 10% off. 1.00 = 100% 0.10 = 10% 0.01 = 1% if you multiply 50 by 0.10 instead you get the amount that is discounted instead of the new selling price.
B, y goes up 8, when you add 8 to y