a) 10 -2x = 25 -3x => -2x +3x = 25 -10 => x =15

b) 2.( |x+1| -3 ) -1 =7 =.> 2.( |x+1| -3) = 7+1 => 2 |x+1| -6 = 8 => 2 |x+1| = 8+6 => 2|x+1| =14=> |x+1| =7

+ x+1 =7 => x =6 hoặc x+1 =- 7 => x =-7 -1 =-8

c) | 2x-5| =7 => 2x -5 =7 => 2x =12 => x =6

                  hoặc 2x -5 = -7 => 2x = -2 => x =-1