70 - 5 . ( 2.x - 3 ) = 45
5( 2x -3 ) = 70 - 45
5( 2x-3 ) = 25
2x-3 = 5
2x = 8
x = 4
70 - 5 . ( 2 . x - 3 ) = 45
5 . ( 2 . x - 3 ) = 70 - 45
5 . ( 2 . x - 3 ) = 25
2 . x - 3 = 25 : 5
2 . x - 3 = 5
2 . x = 5 + 3
2 . x = 8
x = 8 : 2
x = 4
70 - 5(2.x - 3) = 45
5(2.x - 3) = 70 - 45
5(2.x - 3) = 25
2.x - 3 = 25 : 5
2.x - 3 = 5
2.x = 3 + 5
2.x = 8
x = 8 : 2
x = 4
- Chúc cậu học tốt
70 - 5 . (2 . x - 3) = 45
<=> 5 . (2 . x - 3 ) = 70 -45
<=> 5 . (2 . x - 3 ) = 25
<=> 2 . x - 3 = 25 : 5
<=> 2 . x - 3 = 5
<=> 2 . x = 5+3
<=> 2 . x = 8
<=> x = 8 : 2
=> x=4
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