Trl :
425 + 6( 6X - 8 ) = 455
425 + 36X - 48 = 455
377 + 36X = 455
36X = 455 - 377
36X = 78
X = 78 : 36
X = 13/6
Hok tốt
425 + 6( 6x - 8 ) = 455
=>6( 6x - 8 ) = 455 - 425
=>6( 6x - 8 ) =30
=> 6x - 8 = 30 : 6
=> 6x - 8 = 5
=> 6x =5+8
=> 6x= 13
=> x=\(\frac{13}{6}\)
425 + 6(6x - 8) = 455
6( 6x - 8 ) = 455 - 425
6( 6x - 8 ) = 30
(6x - 8) = 30 : 6
6x - 8 = 5
6x = 8 + 5
6x = 13
x = 13 : 6
x =