8)4(x-2)-2(x-1)=12
4x-8-(2x-2)=12
4x-8-2x+2=12
2x-8+2=12
2x=12-2+8
2x=18
x=18/2=9
9)6x-13-2-(x×5)=7
6x-5x=7+13+2
x=22
10)7(x-5)-3(x+5)=30
7x-35-(3x+15)=30
7x-35-3x-15=30
4x=30+35+15
4x=80
x=20
8)4(x-2)-2(x-1)=12
\(\Rightarrow4x-8-2x+2=12\)
\(\Rightarrow2x=18\)
\(=>x=9\)
9)6x-13-2-(x×5)=7
\(\Rightarrow6x-15-\left(x+5\right)=7\)
\(\Rightarrow6x-15-x-5=7\)
\(\Rightarrow5x=27\)
\(\Rightarrow x=\frac{27}{5}\)
10)7(x-5)-3(x+5)=30
\(\Rightarrow7x-35-3x-15=30\)
\(\Rightarrow4x=80\)
\(\Rightarrow x=20\)
8) 4.( x - 2 ) - 2.( x - 1 ) = 12
4x - 8 - 2x + 2 = 12
2x = 12 + 8 - 2
2x = 18
x = 9
Vậy x = 9
9) 6x - 13 - 2 - 5x = 7
x = 13 + 2 + 7
x = 22
Vậy x = 22
10) 7.( x - 5 ) - 3.( x + 5 ) = 30
7x - 35 - 3x - 15 = 30
4x = 35 + 15 + 30
4x = 80
x = 20
Vậy x = 20
8) 4(x-2)-2(x-1)=12
4x-4.2-2x+2.1=12
4x-8-2x+2=12
4x-2x-8+2=12
2x-6=12
2x=12+6
2x=18
x=18:2
x=9
Vậy x=9
9) 6x-13-2-(x.5)=7
6x-15-(x.5)=7
6x-(x.5)=7+15
6x-5x=22
x=22
Vậy x=22
10) 7(x-5)-3(x+5)=30
7x-7.5-3x-3.5=30
7x-35-3x-15=30
7x-3x-35-15=30
4x-50=30
4x=30+50
4x=80
x=80:4
x=20
Vậy x=20
