3x(x+2):7=120:4=30
3x(x+2)=30x7=210
( 3 x ( x + 2 ) : 7 ) x 4 = 120
( 3 x ( x + 2 ) : 7 ) = 120 : 4
3 x ( x + 2 ) : 7 = 30
( x + 2 ) : 7 = 30 : 3
( x + 2 ) : 7 = 10
( x + 2 ) = 10 x 7
x + 2 = 70
x = 70 - 2
x = 68
[ 3 x ( x + 2 ) : 7 ] x 4 = 120
( x + 2 ) : 7 = 120 : 4 :3 = 10
x+ 2 = 10 x 7 = 7
x= 70 - 2 =68
[ 3 x ( x + 2 ) : 7 ] x 4 = 120
[ 3 x ( x + 2 ) : 7 ] = 120 : 4
[ 3 x ( x + 2 ) : 7 ] = 30
3 x ( x + 2 ) = 30 x 7.
3 x ( x + 2 ) = 210
( x + 2 ) = 210 : 3;
( x + 2 ) = 70
x = 70 - 2
x = 68
[3*(x+2):7]x4=120
=> 3* (x+2): 7 = 120: 4 = 30
=> 3* (x+2) = 30 x 7 = 210
=> x+2 = 210 : 3 = 70
=> x = 70 - 2 = 68
Vậy x = 68 ^^
[ 3 x ( x + 2 ) : 7 ] x 4 = 120
[ 3 x ( x + 2 ) : 7 ] = 120 : 4
[ 3 x ( x + 2 ) : 7 ] = 30
3 x ( x + 2 ) = 30 x 7.
3 x ( x + 2 ) = 210
( x + 2 ) = 210 : 3;
( x + 2 ) = 70
x = 70 - 2
x = 68
[3x(x+2):7]x4=120
3x(x+2):7=120:4
3x(x+2)=30x7
x+2=210:3
x+2=70
x=70-2
x=68
Vậy x=68
Cuối mỗi câu tìm x em nên có kết luận Vậy x=... nha,thế khoa học hơn
Chúc em học tốt^^
3 x ( x + 2 ) : 7 x 4 = 120
3 x ( x + 2 ) : 7 = 120 : 4
3 x ( x + 2 ) : 7 = 30
3 x ( x + 2 ) = 30 x 7
3 x ( x + 2 ) = 210
( x + 2 ) = 210 : 3
x + 2 = 70
x = 70 - 2
x = 68
Vậy x = 68
[3x(x+2):7]=120:4
[3x(x+2):7]=30
(X+2):7=30:3
(X+2):7=10
(X+2)=10x7
X+2=70
X=70-2=68
đáp số:x=68
ai k mk mk sẽ k lại cho @@ ủng hộ nhe ^_^
[3.(x+2):7].4=120
[3.(x+2):7]=120:4
[3.(x+2):7]=30
(x+2):7=30:3
(x+2):7=10
(x+2)=10.7
(x+2)=70
x+2=70
x=70-2
x=68
CHÚC BẠN HỌC TỐT!:)
3 x ( x + 2 ) : 7 x 4 = 120
3 x ( x + 2 ) : 7 = 120 : 4
3 x ( x + 2 ) : 7 = 30
3 x ( x + 2 ) = 30 x 7
3 x ( x + 2 ) = 210
( x + 2 ) = 210 : 3
x + 2 = 70
x = 70 - 2
x = 68
[3x(x+2)x4=120 =>3(x+2):7=30 =>3(x+2)=210 =>x+2=70 => 68 vậy x=68