C2: Tìm x a) x – 1/2 = -3/4 b) 2/7 . x = -1/6 c) ( 3/7 . x + 1 ) : ( -4 ) = -1/28 07/07/2021 Bởi Genesis C2: Tìm x a) x – 1/2 = -3/4 b) 2/7 . x = -1/6 c) ( 3/7 . x + 1 ) : ( -4 ) = -1/28
a) x – 1/2 = -3/4 x = -3/4 + 1/2 x = -3/4 + 2/4 x = -1/4 b) 2/7 . x = -1/6 x = -1/6 : 2/7 x = -1/6 . 7/2 x = -7/12 c) ( 3/7 . x + 1 ) : (-4 ) = -1/28 3/7 . x + 1 = -1/28 . (-4) 3/7 . x + 1 = 1/7 3/7 . x = 1/7 – 1 3/7 . x = 1/7 – 7/7 3/7 . x = -6/7 x = -6/7 : 3/7 x = -6/7 . 7/3 x = -2 Bình luận
`a)x-1/2=(-3/4)` `=>x=(-3/4)+1/2``=>x=(-1/4)``b)2/7 . x=(-1/6)``=>x=(-1/6):2/7``=>x=(-7/12)``c)(3/7 .x+1):(-4)=(-1/28)``=>3/7 . x+1=(-1/28).(-4)``=>3/7 . x+1=1/7``=>3/7 .x=1/7-1``=>3/7 . x=(-6/7)``=>x=(-6/7):3/7``=>x=(-2)` Bình luận
a) x – 1/2 = -3/4
x = -3/4 + 1/2
x = -3/4 + 2/4
x = -1/4
b) 2/7 . x = -1/6
x = -1/6 : 2/7
x = -1/6 . 7/2
x = -7/12
c) ( 3/7 . x + 1 ) : (-4 ) = -1/28
3/7 . x + 1 = -1/28 . (-4)
3/7 . x + 1 = 1/7
3/7 . x = 1/7 – 1
3/7 . x = 1/7 – 7/7
3/7 . x = -6/7
x = -6/7 : 3/7
x = -6/7 . 7/3
x = -2
`a)x-1/2=(-3/4)`
`=>x=(-3/4)+1/2`
`=>x=(-1/4)`
`b)2/7 . x=(-1/6)`
`=>x=(-1/6):2/7`
`=>x=(-7/12)`
`c)(3/7 .x+1):(-4)=(-1/28)`
`=>3/7 . x+1=(-1/28).(-4)`
`=>3/7 . x+1=1/7`
`=>3/7 .x=1/7-1`
`=>3/7 . x=(-6/7)`
`=>x=(-6/7):3/7`
`=>x=(-2)`