a,5-(x-6)=4(3-2x)
(=)5-x+6=12-8x
(=)11-x=12-8x
(=)11-x-12+8x=0
(=)7x-1=0
(=)7x=1
(=)x=1/7
S={1/7}
c,7-(2x+4)=-(x+4)
(=)7-2x-4=-x-4
(=)7-2x-4+x+4=0
(=)-x+7=0
(=)-x=-7
(=)x=7
S={7}
Câu e mình ko rõ pt = mấy
g,(x-1)-(x-1)=9-x
(=)x-1-x+1=9-x
(=)0=9-x
(=)-9=-x
(=)9=x
S={9}
h,(x-3)(x+4)-2(3x-2)=(x-4)
(=)x²+4x-3x-12-6x+4=x-4
(=)x²+x-12-6x+4-x+4=0
(=)x²-6x-4=0
=) x=6,605 ( mình bấm nghiệm nên khó để nói thành lời lắm )