Bài 3 mik gửi ảnh ở dưới r nhé.

18x - 19 = 21 + 8x

<=> 18x - 8x = 21 + 19

<=>        10x = 40

<=>            x = 4

Vậy x = 4

g)    18 - 4x = -20 - 6x

<=> -4x + 6x = -20 - 18

<=>          2x = -38

<=>            x = -19

Vậy x = -19 

h)     -15 x 24 = -7x + 32

<=> -360 = -7x + 32

<=> 7x = 360 + 32

<=> 7x = 392

<=>   x = 56

Vậy x = 56

i)      15x - 3(4x - 6) = -12 + 36

<=> 15x - 12x + 18 = 24

<=> 3x = 24 - 18

<=> 3x = 6

<=> x = 2

Vậy x = 2

k)     -10 x - 27 = -7x + 33

<=> -10x + 7x = 33 + 27

<=>     -3x = 60

<=>        x = -20

Vậy x = -20 

m)    -17 x (-24) = -9x - 40

<=> 408 = -9x - 40

<=> 9x = -40 - 408

<=> 9x = -448

<=> x = -$\frac{448}{9}$ 

Vậy x = -$\frac{448}{9}$ 

n)     -23 x 25 = -18x + 75

<=> -575 = -18x + 75

<=> 18x = 75 + 575

<=> 18x = 650

<=>    x = $\frac{325}{9}$ 

Vậy x = $\frac{325}{9}$ 

p)     -5x + 7(2x - 3) = 4(x - 4)

<=> -5x + 14x - 21 = 4x - 16

<=> -5x + 14x - 4x = -16 + 21

<=> 5x = 5

<=>  x = 1

Vậy x = 1

q)     24 - 6(3x + 1) = -5(4x - 4) - 8

<=> 24 - 18x - 6 = -20x + 20 - 8

<=> -18x + 20x = 20 - 8 - 24 + 6

<=>   2x = -6

<=>    x = -3

Vậy x = -3

r)      18 - 4.(6 - 2x) = -3.(4x + 5) - 11

<=> 18 - 24 + 8x = -12x - 15 - 11

<=>  8x + 12x = -15 - 11 - 18 + 24

<=>   20x = -20

<=>      x = -1

Vậy x = -1

s)     -5.(4x - 5) - 14 = 6.(2 - 3x) - 10x - 9

<=> -20x + 25 - 14 = 12 - 18x - 10x - 9 

<=> -20x + 18x + 10x = 12 - 9 - 25 + 14

<=> 8x = -8

<=>   x = -1

Vậy x = -1

a) 18x-19=21+8x=>10x=40=>x=4

g) 18- 4x = -20-6x=>2x=-38=>x=-19

i) 15x- 3(4x - 6) = - 12+ 36=>15x-12x+18=-12+36=>3x=6=>x=2

k) -10 x - 27 = - 7x +33=>-3x=60=>x=-20

m) -17 x - 24 = - 9x - 40=>8x=-16=>x=-3

p) - 5x+ 7( 2x-3) = 4( x - 4)=>-5x+14x-21=4x-16=>15x=5=>x=3

q)24- 6(3x + 1) = -5( 4x- 4 ) - 8=>24-18x-6=-20x+20=>2x=-10=>x=-5