Tìm x :
346 . 124 - 7 . ( 2x - 1 ) = 346
7 . ( 2x - 1 ) = ( 346 . 124 ) - 346
7. ( 2x - 1 ) = 346 . 123
7 . 2x - 7 .1 = 42558
7 . 2x = 42558 - 7
7.2. x = 42551
14 . x = 42551
=> x = \(\dfrac{42551}{14}\)
Vậy : x = \(\dfrac{42551}{14}\)
b) \(\dfrac{4}{3}\) +2 . ( 5 + 7x ) = 115 : 5
\(\dfrac{4}{3}\) + 2. 5 + 2 . 7.x = 23
\(\dfrac{4}{3}\) + 10 + 14 . x = 23
\(\dfrac{4}{3}\) + 24 . x = 23
=> \(\dfrac{76}{3}\) . x = 23
=> x = 23 : \(\dfrac{76}{3}\)
=> x = \(\dfrac{69}{76}\)
Vậy x = \(\dfrac{69}{76}\)
