Seek several factorization! x^2+9x+20 x^2-5x+6 x^2+x-2 x^2+x-2 x^2+x-2 x^2-3x-18 -x^2+7x-12 -x^2-x+6 2x^2-4x-30 -5x^2+25x+120

Seek several factorization! x^2+9x+20 x^2-5x+6 x^2+x-2 x^2+x-2 x^2+x-2 x^2-3x-18 -x^2+7x-12 -x^2-x+6 2x^2-4x-30 -5x^2+25x+120

x^2+9x+20=(x+5)(x+4)
x^2-5x+6=(x-3)(x-2)
x^2+x-2=(x-1)(x+2)
x^2+x-2=(x-1)(x+2)
x^2+x-2=(x-1)(x+2)
x^2-3x-18=(x-6)(x+3)
-x^2+7x-12=(4-x)(x-3)
-x^2-x+6=(x+3)(2-x)
2x^2-4x-30==2(x^2-2x-15)=2(x-5)(x+3)
-5x^2+25x+120=5(-x^2+5x+24)=5(8-x)(x+3)

1000 square - 999 square + 998 square - 997 square +Square of 2 - square of 1=

1000 square - 999 square + 998 square - 997 square +Square of 2 - square of 1=
=(1000+999)(1000-999)+(998+997)(998-997)+.+(2+1)(2-1)
=1000+999+998+997+.+2+1
=(1000+1)×1000÷2
=500500

Factorization of review question 9 in grade one
1.2a(a-3)²-6a²(3-a)+8a(a-3)
2.2a(x²+1)²-8ax²

(1) (4a-1)(a-3)2a
(2) 2a(X^2-1)(X^2-1)