Ineed some algebraic so i don't fail.

(x-y)^2 +4xy = (x+y)^2

FOIL

x^2 -2xy+y^2 +4xy = (x+y)^2             x^2 -2xy

Combine like terms

x^2 +2xy +y^2 =  (x+y)^2                   x^2 +2xy

Factor

(x+y)^2 = (x+y)^2                                 (x+y)^2  

she would want to sell 10 full-year subscriptions and at least 9 half-year subscriptions to get a total of at least $300. 

i hope this answer you! if you have any further questions or concerns, feel free to ask! : )

step-by-step explanation:

mark brainliest!