Question 194182
try
3a -3b -a^2 +b^2
,
3 (a-b) - ( a^2 -b^2 )
3 (a-b) - (a+b) (a-b)
,
(a-b) (3-(a+b) )
(a-b) (3-a-b)
,
check  to  original  by  distributing,,,all,,ok