Respuesta :
I think this is what your doing am assuming . forgot but just put -3a+1a solve it and then do -1+2 and you got your anwser
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distribute and add like terms
-(6a³-3a+8)=-6a³+3a-8
now add
3a²+4a-6-6a³+3a-8
regroup
-6a³+3a²+4a+3a-6-8
-6a³+3a²+7a-14
dat is expanded and compacted
-(6a³-3a+8)=-6a³+3a-8
now add
3a²+4a-6-6a³+3a-8
regroup
-6a³+3a²+4a+3a-6-8
-6a³+3a²+7a-14
dat is expanded and compacted