Question

484 в,г!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

$(3a+b)(a-b)-(2a^2-b^2) = 3a^2-3ab+ab-b^2-2a^2+b^2=a^2-2ab\\\\(a-3)(a+3)-9a^2 = a^2-9-9a^2 = -8a^2-9$