a) x(x+2)=0
(x+1)(x+4)=0
z(z-1,6)=0
(y+2)(e-6)=0
хоть один)

1) х(x+2) = 0
x = 0 ______ x + 2 = 0
                      x = -2

2) z (z-1,6) = 0

z=0 ____ z -1,6=0

              z=1,6

3) (y+2)(y-6) = 0

y^2 - 6y + 2y -12 = 0

y^2 - 4y - 12=0

y1 =  6   y2 = - 2

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

x^2 + 4x + x+4 = 0

x^2 +5x+4 =0

D = 5^2 -4*4 = 25-16=9
D = 3
x1= -5+3/2 = -2/2 = -1  

x2 = -5-3/2 = -8/2 = -4