Преобразуйте в многочлен: a) 4(m-n)²+4m(m-n). в) (y+7)²-2(y+10)(y+4)

4( m^2 - 2mn + n^2) + 4m^2 - 4mn = 4m^2 - 8mn  + 4n^2 + 4m^2 - 4mn =
= 8m^2 - 12mn + 4n^2

y^2 + 14y + 49 - 2( y^2 + 14y + 40) = y^2+14y+49 -2y^2- 28y - 80 =
= - y^2 - 14y - 31