Question

|3x+5x|-2x=9-3x

Answer 1

|3x + 5x| - 2x = 9 - 3x

<=> |8x| = 9 - x    (1)

TH1: x ≥ 0

=> |8x| = 8x

=> (1) <=> 8x = 9 - x

<=> 9x = 9

<=> x = 1 (TM)

TH2: x < 0

=> |8x| = -8x

=> (1) <=> -8x = 9 - x

<=> -7x = 9

<=> x = -9/7 (TM)

vậy x ∊ {1; -9/7}

Answer 2

|3x+5x|-2x=9-3x

=>|8x| = 9 - x  

TH1: x ≥ 0

=> |8x| = 8x

=> |8x| = 9 - x  <=> 8x = 9 - x

<=> 9x = 9

<=> x = 1 (TM)

TH2: x < 0

=> |8x| = -8x

=> (1) <=> -8x = 9 - x

<=> -7x = 9

<=> x = -9/7 (TM)

vậy x ∊ {1; -9/7}