(1)-110-x+x^2
(2)x^2-(m+n)x+mn
(3)x^2-(2a-b)x-2ab
(4)x^2-(a-b)x-ab
(5)x^2-(a+1)x+a
(6)x^2+ax+2(a-2)
(7)x^2y^2+xy-12
(1)-110-x+x^2
(2)x^2-(m+n)x+mn
(3)x^2-(2a-b)x-2ab
(4)x^2-(a-b)x-ab
(5)x^2-(a+1)x+a
(6)x^2+ax+2(a-2)
(7)x^2y^2+xy-12
(1)-110-x+x^2=(x-11)(x+10)
(2)x^2-(m+n)x+mn=(x-m)(x-n)
(3)x^2-(2a-b)x-2ab=(x-2a)(x+b)
(4)x^2-(a-b)x-ab=(x-a)(x+b)
(5)x^2-(a+1)x+a=(x-a)(x-1)
(6)x^2+ax+2(a-2)=(x+2)(x+a-2)
(7)x^2y^2+xy-12=(xy+4)(xy-3)