4x+4=0

x=- 1

& lt2>a is not equal to 0.

4? -4*4*a=0

a= 1

x=-2

To sum up: a=0, x=- 1 or a= 1, x=-2.

2. It should be [2a, a? -a]？

If so, then:

Answer? -a & gt； 2a

Answer? -3a & gt； 0

a(a-3)>0

A>3 or a<0