cứuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuBài 2: Tìm số tự nhiên x, biết:
b) (156-9x+61)=82
e) 12.[43-(56-x)]=384
g) 144: (8.x-76)

Question

cứuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

ngocpham1204 · Answer

` \color{#0074D9}{#n}\color{#0088DD}{q}\color{#3399FF}{o}\color{#66AAFF}{c}\color{#99CCFF}{c} `
`b) (156 - 9x + 61) = 82 `
`(217 - 9x) = 82 `
`217 - 9x = 82 `
`9x = 135 `
`x = 135 : 9 `
`x = 15 `
Vậy `x=15 `
`c) 12 : (3x - 7) + 34 = 40 `
`12  : (3x-7) = 40 - 34 `
`12 : (3x-7) = 6 `
`(3x-7) = 12 : 6 `
`3x-7= 2 `
`3x = 2 + 7 `
`3x = 9 `
`x = 9 : 3 `
`x = 3 `
Vậy `x=3`
`d) 101 + (105 : x - 12).7 = 122 `
`(105 : x - 12).7 = 122 - 101 `
`(105 : x - 12).7 = 21 `
`(105 : x - 12) = 21 : 7 `
`105 : x - 12 = 3 `
`105 : x = 3 + 12 `
`105 : x = 15 `
`x = 105 : 15 `
`x= 7`
Vậy `x=7`
`e) 12 . [43 - (56 - x)]=384 `
`12. [43 - 56 + x]=384 `
`12 . [-13 + x] = 384 `
`(-13 + x) = 384 : 12 `
`-13 + x = 32 `
`x = 32 - (-13) `
`x = 45 `
Vậy `x=45`
`f) 26 - 3.(x-5) = 14 `
`3(x-5) = 26 - 14 `
`3(x-5) = 12 `
`(x-5) = 12 : 3 `
`x-5 = 4 `
`x = 4 + 5 `
`x = 9 `
Vậy `x=9`
`g) 144 : (8x - 76) = 36 `
`(8x - 76) = 144 : 36 `
`8x - 76 = 4 `
`8x = 4 + 76 `
`8x = 80 `
`x = 80 : 8 `
`x = 10 `
Vậy `x=10`
`h) 7(x-6) = 4x + 9 `
`7x - 42 = 4x + 9 `
`7x - 4x = 42 + 9 `
`3x = 51 `
`x = 51 : 3 `
`x = 17 `
Vậy `x=17`

dotuelinh13 · Answer

Đáp án`+`Giải thích các bước giải:
 Bài `2`:
`b)` `(156 - 9 x + 61 ) = 82`
`156 - 9x = 82 - 61`
`156 - 9x = 21`
`9x = 156 - 21`
`9x = 135`
`x = 135 : 9`
`x = 15`
Vậy `x = 15`
`c)` `12 : ( 3 x - 7 ) + 34 = 40`
`12 : ( 3 x - 7 ) = 40 - 34`
`12 : ( 3 x - 7 ) = 6`
`3 x - 7 = 12 : 6`
`3 x - 7 = 2`
`3 x = 2 + 7`
`3 x = 9`
`x = 9 : 3`
`x = 3`
Vậy `x = 3`
`d)` `101 + ( 105 : x - 12 ) . 7 = 122`
`( 105 : x - 12 ) . 7 = 122 - 101`
`( 105 : x - 12 ) . 7 = 21`
`105 : x - 12 = 21 : 7`
`105 : x - 12 = 3`
`105 : x = 3 + 12`
`105 : x = 15`
`x = 105 : 15`
`x = 7`
Vậy `x = 7`
`e)` `12 . [ 43 - ( 56 - x ) ] = 384`
`43 - ( 56 - x ) = 384 : 12`
`43 - ( 56 - x ) = 32`
`56 - x = 43 - 32`
`56 - x = 11`
`x = 56 - 11`
`x = 45`
Vậy `x = 45`
`f)` `26 - 3 . ( x - 5 ) = 14`
`3 . ( x - 5 ) = 26 - 14`
`3 . ( x - 5 ) = 12`
`x - 5 = 12 : 3`
`x - 5 = 4`
`x = 4 + 5`
`x = 9`
Vậy `x = 9`
`g)` `144 : ( 8 . x - 76 ) = 36`
`8 . x - 76 = 144 : 36`
`8 . x - 76 = 4`
`8 . x = 4 + 76`
`8 . x = 80`
`x = 80 : 8`
`x = 10`
Vậy `x = 10`
`h)` `7 . ( x - 6 ) = 4 x + 9`
`7 x - 42 = 4x + 9`
`7x - 4x = 9 + 42`
`3x = 51`
`x = 51 : 3`
`x = 17`
Vậy `x = 17`

cứuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

TRẢ LỜI

Bạn muốn hỏi điều gì?

Tham Gia Group Dành Cho Lớp 6 Chia Sẻ, Trao Đổi Tài Liệu Miễn Phí

Bạn muốn hỏi điều gì?

Tìm kiếm với hình ảnh

Hãy đăng nhập hoặc tạo tài khoản miễn phí!

Lưu vào

cứuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

TRẢ LỜI

Bạn muốn hỏi điều gì?

Tham Gia Group Dành Cho Lớp 6 Chia Sẻ, Trao Đổi Tài Liệu Miễn Phí

Bạn muốn hỏi điều gì?

Lý do báo cáo vi phạm?