5x+2x^2=0 -2x^2-4x=0
5x+2x^2=0 2x^2 + 5x = 0 x ( 2x + 5) = 0 x = 0 или 2x + 5 = 0 2x = -5 x = -2,5 -2x^2-4x=0 / (-2) x^2 + 2x = 0 x ( x +2) = 0 x = 0 или x + 2 = 0 x = -2
X(5+2x)=0 2x(-x-2)=0 x=0 и 2x=-5 2x=0 и -x=2 x=-2.5 x=-2