`a, 8 . 5^2 - { 120 - [ 868 - 12 . ( 3087 : 7^2 + 7^0 )]}`
`= 8 . 25 - { 120 - [ 868 - 12 . ( 3087 : 49 + 1 )]}`
`= 200 - { 120 - [ 868 - 12 . 64 ]}`
`= 200 - { 120 - 100 }`
`= 200 - 20`
`= 180`
`b, 4^11 . 4 : 4^12 + | 2015^0 |`
`= 1 . | 1 |`
`= 1 . 1`
`= 1`
`c, 127 - ( 2^3 . 7 + 3^4 : 3 )`
`= 127 - ( 8 . 7 + 3^3 )`
`= 127 - ( 56 + 27 )`
`= 127 - 83`
`= 44`
`d, 167 - 3 ( x + 4 ) = 140`
`3 ( x + 4 ) = 167 - 140`
`3 ( x + 4 ) = 27`
`x + 4 = 27 : 3`
`x + 4 = 9`
`x = 9 - 4`
`x = 5`
`Vậy` `x = 5`
`e, 12 ( x - 3 ) : 3 = 4^2 - 2^3`
`12 ( x - 3 ) : 3 = 16 - 8`
`12 ( x - 3 ) : 3 = 8`
`12 ( x - 3 ) = 8 . 3`
`12 ( x - 3 ) = 24`
`x - 3 = 24 : 12`
`x - 3 = 2`
`x = 2 + 3`
`x = 5`
`Vậy` `x = 5`
`f, [ ( 8x - 14 ) : 2 - 1 ] . 41 = 451`
`( 8x - 14 ) : 2 - 1 = 451 : 41`
`( 8x - 14 ) : 2 - 1 = 11`
`( 8x - 14 ) : 2 = 11 + 1`
`( 8x - 14 ) : 2 = 12`
`8x - 14 = 12 . 2`
`8x - 14 = 24`
`8x = 24 + 14`
`8x = 38`
`x = 4,75`
`Vậy` `x = 4,75`
Câu cuối hơi lạ :'>
