Bạn ơi, lần sau cho thêm xu nha, bài dài quá :(
a) -2x – (x – 17) = 34 – (-x + 25)
=> - 2x - x + 17= 34 + x - 25
=> - 3x - x = 34 - 25 - 17
=> - 4x = -8
=> 8 = 4x
=> x = 8:4 = 2
b) 17x – (-16x – 37) = 2x + 43
=> 17x + 16x + 37 = 2x + 43
=> 17x + 16x - 2x = 43 - 37
=> 31x = 6
=> x = 6/31
c) -2x –3. (x – 17) = 34 – 2(-x + 25)
=> - 2x - (3x - 51) = 34 - (-2x + 50)
=> - 2x - 3x + 51 = 34 +2x - 50
=> 51 - 34 + 50 = 2x + 3x + 2x
=> 67 = 7x
=> x = 67/7
d) 17x + 3. (-16x – 37) = 2x + 43 - 4x
=> 17x + (- 48x - 111) = 2x + 43 - 4x
=> 17x - 48x - 111 = 2x + 43 - 4x
=> 17x - 48x - 2x + 4x = 43 + 111
=> -29x = 154
=> x = 154/-29
e) -103 -57: [-2. (2x – 1)2 – (-9)0] = -106
=> - 103 - 57 : [-2. (2x- 1). 2 + 9.0] = -106
=> - 103 - 57 : [-8x-(-4) + 0] = -106
=> - 103 - 57 : (-8x + 4) = -106
=> - 57 : (- 8x + 4) = - 106 + 103
=> - 57 : (- 8x + 4) = 3
=> (- 8x + 4) = 57 : 3
=> - 8x + 4 = 19
=> -8x = 15
=> x = 15/-8
f) - 2x + 3 (12-2[3x-(20+2x)-4x]+1) = 45
=> - 2x + 3 (12-2[3x-20-2x-4x]+1) = 45
=> - 2x + 3 (12-6x-40-4x-8x+1) = 45
=> - 2x + 3 (12-40+1-6x-4x-8x) = 45
=> - 2x + 3 (-27-18x) = 45
=> - 2x + (-81 - 54x) = 45
=> - 2x - 81 - 54x = 45
=> - 56x = 45 + 81
=> - 56x = 126
=> x = 126/-56
g) 3x – 32 > -5x + 1
=> 3x - 33 > - 5x
=> 8x - 33 > 0
=> 8x > 33
=> x > 33/8
h) 15 + 4x < 2x – 145
=> 15 + 2x <- 145
=> 160 + 2x < 0
=> 2x < -160
=> x < -160/2
i) -3. (2x + 5) -16 < -4. (3 – 2x)
=> - 9x + (- 15) - 16 < -12 - (-8x)
=> - 9x - 15 - 16 < -12 + 8x
=> - 9x - 31 < - 12 + 8x
=> - 9x - 19 < 8x
=> - 17x - 19 < 0
=> - 17x < 19
=> x <10/-17
k) -2x + 15 < 3x – 7 < 19 – x
=> -x + 15 < 4x -7 < 19
=> 15 < 5x - 7 < 19 + x
=> 22 < 5x < 26 + x
=> 5x < 26 + x
=> 4x < 26
=> x < 4
Thui, tui lười lắm, tự làm l,m đi :)
