a) Ta có: 5 .(x+4) = 123 - 38
5 .(x+4) = 85
x+4 = 85 : 5
x+4 = 17
x = 17 - 4
x = 13
Câu b: Tương tự
a) 5 . ( x + 4 ) = 123 - 38
5 . ( x + 4 ) = 85
x + 4 = 85 : 5
x + 4 = 17
x = 17 - 4
x = 13
b ) \(3.x-16=2.7^4:7^3\)
3 . x - 16 = 2 . 7
3 . x - 16 = 14
3 . x =14 + 16
3 . x = 30
x = 30 : 3
x = 10
k mik nhé các bn I LVE YOU VERY MUCH