x=0
x=-1/2
x>=0
2x+1-x=5a
x=5a-1 5a-1>0 a>1/5
x<=-1/2</p>
-2x-1+x=5a
-x-1=5a
x=-1-5a
-(5a+1)<-1/2 5a+1>1/2 5a>-1/2 a>-1/10
(-1/2;0)
2x+1+x=5a
3x=5a-1
x=(5a-1)/3
5a-1<0 a<1/5 5a-1>-3/2 5a>-1/2 a>-1/10
(-1/10;1/5)
a (-1/10;1/5) x=(5a-1)/3 x=-1-5a
a>1/5
x=5a-1
x=(5a-1)/3
x=-1-5a