Question

pomocy... nic z tego nie czajęęęęęęęę! a) 3-11x=-3(x+2)

B) 3(X-2)+4=2(X+1 )

c)3(x-1)=6(x+1)+12

d)1/4+2/5 x +1/4=2

e)2/3 x - 1/2=4

f)3/7x-1=x

G)(4x-6):2-6x=2

pomocy+ to ma być na poziomie SP!

Answer 1

B)

3(x-2)+4=2(x+1 )

 

3x - 6 +4 = 2x + 2

 

3x - 2= 2x + 2

 

3x - 2x= 2 + 2

 

x= 4

 

 

spr.

 

3(x-2)+4=2(x+1 )

 

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

 

3*2 + 4= 2*5

 

6 + 4= 10

 

10 = 10

 

 

 

 

 

c)

3(x-1)=6(x+1)+12

 

3x - 3 = 6x + 6 + 12

 

3x -3 = 6x + 18

 

3x - 6x = 18 + 3

 

-3x= 21

 

x= 21 : (-3)

 

x= - 7

 

 

spr.

 

3(x-1)=6(x+1)+12

 

3(-7 -1) = 6(-7 + 1) + 12

 

3*(-8) = 6*(-6) + 12

 

- 24= -36 + 12

 

-24= -24

 

 

 

 

d)

1/4+2/5 x +1/4=2

 

2/5x + 2/4= 2

 

2/5x= 2 - 2/4

 

2/5x= 1 i 2/4

 

x= 1 i 2/4 : 1/5

 

x= 6/4 : 2/5

 

x= 6/4 * 5/2

 

x= 3/4 * 5/1

 

x= 15/4

 

x= 3 i 3/4

 

 

spr.

 

1/4+2/5 x +1/4=2

 

2/5 * 15/4 + 2/4 = 2

 

1/1 * 3/2 + 2/4= 2

 

3/2 + 1/2= 2

 

4/2=2

 

2=2

 

 

 

 

 

 

e)

2/3 x - 1/2=4  

 

2/3x= 4 + 1/2

 

2/3x = 4 i 1/2

 

x= 9/2 : 2/3

 

x= 9/2 * 3/2

 

x= 27/4

 

x= 6 i 1/4

 

 

spr.

 

2/3 x - 1/2=4  

 

2/3 * 27/4 - 1/2= 4

 

1/1 * 9/2 - 1/2 = 4

 

9/2 - 1/2= 4

 

8/2= 4

 

4=4

 

 

 

 

 f)

3/7x-1=x

 

3/7x - x= 1

 

- 4/7x = 1

 

x= 1 : (-4/7)

 

x= 1 *(-7/4)

 

x= - 7/4

 

x= - 1 i 3/4

 

 

 

spr.

 

3/7x-1=x

 

3/7 * (-7/4) - 1 = - 7/4

 

3/1 *(-1/4) - 1= - 1 i 3/4

 

- 3/4 - 1= - 1 i 3/4

 

- 1 i 3/4 = - 1 i 3/4

 

 

 

 

g)

(4x-6):2-6x=2

 

2x - 3 - 6x= 2

 

- 4x - 3= 2

 

-4x = 2 + 3

 

- 4x= 5

 

x= 5 : (-4)

 

x= - 5/4

 

x= - 1 i 1/4

 

 

 

spr.

 

(4x-6):2-6x=2

 

(4 * (-5/4) - 6): 2 - 6*(-5/4) = 2

 

(1* (-5/1) - 6) : 2- 3*(-5/2) = 2

 

(-5 - 6) : 2 - (-15/2) = 2

 

-11 : 2 + 15/2= 2

 

- 11/2 + 15/2= 2

 

4/2 = 2

 

2=2