Question

Tìm x biết: 3. (4 – x) – 2. ( x- 1) = x + 20

Answer 1

Tìm x biết: 3. (4 – x) – 2. ( x- 1) = x + 20

12 - 3x - 2x + 2 = x + 20

-5x + 14 = x + 20

-5x + 14 - x - 20 =0

-6x - 6 = 0

-6x      = 6

   x       = -1

Answer 2

 3. (4 – x) – 2. ( x- 1) = x + 20

\(=>12-3x-2x+2=x+20\)

\(=>14-5x-x-20=0\)

\(=>-6-6x=0=>-6\left(1+x\right)=0=>1+x=0=>x=-1\)

Vậy x= - 1 

Hok tốt nha !

Answer 3

=> 12-3x-2x+2=x+20

=> 5x=-6

=> x=-6/5

 vậy x=-6/5

Answer 4

\(12-3x-2x+2=x+20\)

\(-5x+14=x+20\)

\(-5+14-x-20=0\)

\(-6x-6=0\)

\(-6x=0+6\)

\(-6x=6\)

\(=>x=-1\)

Answer 5

<=> 12 - 3x - 2x + 2 = x + 20

<=> 12 - 5x + 2 = x + 20

<=> 12 + 2 -20 = x + 5x

<=> - 6 = 6x

=> x = -1

           Vậy x = -1

HOK TỐT

Answer 6

\(3.\left(4-x\right)-2.\left(x-1\right)=x+20\)

\(\Leftrightarrow12-3x-2x+2=x+20\)

\(\Leftrightarrow\left(12+2\right)-\left(3x+2x\right)=x+20\)

\(\Leftrightarrow14-5x=x+20\)

\(\Leftrightarrow-5x-x=20-14\)

\(\Leftrightarrow-6x=6\)

\(\Leftrightarrow x=6:\left(-6\right)\)

\(\Leftrightarrow x=-1\)

Vậy : \(x=-1\)

Rất vui vì giúp đc bạn !!!

Answer 7

3.(4 - x) - 2.(x - 1) = x + 20

=> 12 - 3x - 2x + 2 = x + 20

=> - 3x - 2x - x = 20 - 12 - 2

=> - 6x = 6

=> x = -1

Hok tốt 

Answer 8

\(3\cdot\left(4-x\right)-2\cdot\left(x-1\right)=x+20\)

\(\Rightarrow12-3x-2x+2=x+20\)

\(\Rightarrow14-5x=x+20\)

\(\Rightarrow-5x-x=-14+20\)

\(\Rightarrow-6x=6\)

\(\Rightarrow x=\frac{6}{-6}=-1\)

Vậy x=-1

Answer 9

\(12-3x-2x+2=x+20\)

\(12-3x-2x+2=x+20\)

\(-5x+14=x+20\)

\(\Rightarrow-5x+14-x-20=0\)

\(-6x-6=0\)

\(-6x=6\)

\(x=-1\)