Question

Разложите на множители: 25a^2-1,3x-xy+6-2y,4ab+28a-b^2-7b,3xy-6x-y^2+2y

Answer 1

$1) 25a^2-1=(5a-1)(5a+1)\\2)3x-xy+6-2y=x(3-y)+2(3-2y)=(x+2)(3-2y)\\3)4ab+28a-b^2-7b=4a(b+7)-b(b+7)=(4a-b)(b+7)\\4)3xy-6x-y^2+2y=3x(y-2)-y(y-2)=(3x-y)(y-2)$