1 ) <=> 5.3x = 405
<=> 3x = 81 = 34
=> x = 4
2 ) <=> 2x ( 7.23 - 5.22 + 1 ) = 1184
<=> 2x ( 7.8 - 5.4 + 1 ) = 1184
<=> 2x ( 56 - 20 + 1 ) = 1184
<=> 2x . 37 = 1184
<=> 2x = 32 = 25
=> x = 5
1 ) <=> 5.3x = 405
<=> 3x = 81 = 34
=> x = 4
2 ) <=> 2x ( 7.23 - 5.22 + 1 ) = 1184
<=> 2x ( 7.8 - 5.4 + 1 ) = 1184
<=> 2x ( 56 - 20 + 1 ) = 1184
<=> 2x . 37 = 1184
<=> 2x = 32 = 25
=> x = 5
mk để mk đc trong 290đ đc ko!?