Question

Es por factorizacion, por favor:
x^2+4x=9x
x^2+10x+21=0
x^2-20=-x
x^2-x=0
5x^2-20x=0
x^2+8x+12=0
x^2-6x+9=0
14x+49=-x^2
4x^2+x=0

Answer 1

x^2+4x=9x
x^2+4x-9x=0
x^2-5x=0
x(x-5)

x^2+10x+21=0
(x+3)(x+7)

x^2-20=-x
x^2+x-20=0
(x+5)(x-4)

x^2-x=0
x(x-1)

5x^2-20x=0
5x(x-4)

x^2+8x+12=0
(x+6)(x+2)

x^2-6x+9=0
(x-3)(x-3)

14x+49=-x^2
x^2+14x+49
(x+7)(x+7)

4x^2+x=0
x(4x+1)