Lười làm quá giúp mik nhéee c.ơn

`ttcolor{orange}{@thuyhien}`

Bài `6:`

`1)` `3 - 2 . (x + 1) = -4`

`2 . (x + 1) = 3 - (-4)`

`2 . (x + 1) = 7`

`(x + 1) = 7 : 2`

`x + 1 = 7/2`

`x = 7/2 - 1`

`x = 5/2`

Vậy `x = 5/2`

`2)` `11/15 - (7/9 + x) . 3/8 = 61/90 + 8/3`

`11/15 - (7/9 + x) . 3/8 = 301/90`

`(7/9 + x) . 3/8 = 11/15 - 301/90`

`(7/9 + x) . 3/8 = -47/18`

`(7/9 + x) = -47/18 : 3/8`

`7/9 + x = -188/27`

`x = -188/27 - 7/9`

`x = -209/27`

Vậy `x = -209/27`

`3)` `2/3 - 1/3 . (x - 3/2) - 1/2 . (2x + 1) = 5`

`2/3 - (1/3 . x + 1/3 . 3/2) - (1/2 . 2x + 1/2 . 1) = 5`

`2/3 - 1/3x + 1/2 - x - 1/2 = 5`

`2/3 - (1/3x + x) + (1/2 - 1/2) = 5`

`2/3 - 4/3x = 5`

`4/3x = 2/3 - 5`

`4/3x = -13/3`

`x = -13/3 : 4/3`

`x = -13/4`

Vậy `x = -13/4`

`4)` `15/8 - 1/8 : (x - 1/2) = 5/4`

`1/8 : (x - 1/2) = 15/8 - 5/4`

`1/8 : (x - 1/2) = 5/8`

`(x - 1/2) = 1/8 : 5/8`

`x - 1/2 = 1/5`

`x = 1/5 + 1/2`

`x = 7/10`

Vậy `x = 7/10`

Bài `7:`

`1)` `(3/4)^2 . 4^2 - (1/2)^2 = 2`

`->` Sai đề :D

`2)` `3 - (-2/3)^2 - 2 . (-2/3) + 4 : (-2/3)^0`

`= 3 - 4/9 - 2 . (-2/3) + 4 : 1`

`= 3 - 4/9 - (-4/3) + 4`

`= 23/9 + 4/3 + 4`

`= 35/9 + 4`

`= 71/9`

`3)` `(2/3)^3 - 4 . (-1 3/4)^2 + (-2/3)^3`

`= 8/27 - 4 . 49/16 + (-8/27)`

`= 8/27 - 49/4 - 9/27`

`= 0 - 49/4`

`= -49/4`