Question

Rozwiąż równania i sprawdz ich rozwiązanie

3x-2(x+1)=3+3x

5(x-1)+2x=2(x+1)+8

2(4-x)=5(x-1)-1

2(x-1)-5=3(2x-3)-8x

12x-(2x+1)=9(2-x)

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

Answer 1

3x-2(x+1)=3+3x

3x - 2x - 2 = 3 + 3x

3x -2x -3x = 3 + 2

-2x = 5 | : (-2)

x=  - 2,5

 

-2 * (-2,5) = 5

5=5

__________

5(x-1)+2x=2(x+1)+8

5x - 5 + 2x = 2x + 2 + 8

5 x + 2x - 2x = 2 + 8 + 5

5x = 15 | ; 5

x = 3

 

5*3 = 15

15=15

______________

2(4-x)=5(x-1)-1

8- 2x = 5x - 5 - 1

- 2x - 5 x = -5 - 1 - 8

- 7 x = -14 | : (-7)

x = 2

 

-7*2 = - 14

-14 = - 14

 

_________________

2(x-1)-5=3(2x-3)-8x

2x - 2 - 5 = 6 x - 9 - 8x

2x - 6x + 8 x = - 9 + 2  + 5

4 x = -2 | :4

x = - 1/2

 

4* (-1/2) = -2

-2 = -2

______________

12x-(2x+1)=9(2-x)

12x - 2x - 1 = 18 - 9x

12x - 2 x + 9 x = 18 + 1

19 x = 19 | ; 19

x = 1

19 * 1 = 19

19 = 19

 

_____________

 

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

3x + 3 - 4 = 2x - 4 + 2x

3x - 2x - 2x = -4 - 3 + 4

-1x =  - 3 | : (-1)

x = 3

 

-1 * 3 = - 3

-3 = -3

 

 

Licze na naj :)

Answer 2

a)

3x-2(x+1)=3+3x

3x-2x-2-3-3x=0

-2x-5=0

-5=2x   /:2

x=-5/2

 

spr.

3*(-5/2)-2((-5/2)+1)=3+3*(-5/2)

-15/2-2(-5/2+2/2)=3-15/2

-15/2-2*(-3/2)=6/2-15/2

-15/2+6/2=-9/2

-9/2=-9/2

 

b)

5(x-1)+2x=2(x+1)+8

5x-5+2x=2x+2+8

7x-2x=10+5

5x=15   /:5

x=3

 

spr.

5(3-1)+2*3=2(3+1)+8

5*2+6=2*4+8

10+6=8+8

16=16

 

c)

2(4-x)=5(x-1)-1

8-2x=5x-5-1

8-2x=5x-6

-2x-5x=-6-8

-7x=-14    /:(-7)

x=2

 

spr.

2(4-2)=5(2-1)-1

2*2=5*1-1

4=5-1

4=4

 

d)

2(x-1)-5=3(2x-3)-8x

2x-2-5=6x-9-8x

2x-7=-2x-9

2x+2x=-9+7

4x=-2    /:4

x=-1/2

 

spr.

2(-1/2-1)-5=3(2*(-1/2)-3)-8*(-1/2)

2*(-3/2)-5=3(-1-3)+4

-3-5=3*(-4)+4

-8=-12+4

-8=-8

 

e)

12x-(2x+1)=9(2-x)

12x-2x-1=18-9x

10x-1=18-9x

10x+9x=18+1

19x=19    /:19

x=1

 

spr.

12*1-(2*1+1)=9(2-1)

12-(2+1)=9*1

12-3=9

9=9

 

f)

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

3x+3-4=2x-4+2x

3x-1=4x-4

3x-4x=-4+1

-x=-3     /:(-1)

x=3

 

spr.

3(3+1)-4=2(3-2)+2*3

3*4-4=2*1+6

12-4=2+6

8=8