Question

Zad.9.str.118
a)2x+5=14,8+(x-3)
b)1/4x-(4+1/2x)=-2
c)2(3-x)-4(x-5)=2x+2
d)1/3.(-6x+9)-4=-5(x+1)
e)0,2.(10-5x)=3+2(x-1)
f)37=(20-4x).0,5-7x
2. Zad.11.str.118
a)x-1/2=4,6+3 1/2x
b)7x/2+2x/3=11x+13 2/3
c)2,5x-2/2=8x+0,5/7
d)x-5/8=5x-18/12
e)4/x-2=5/12x-1 1/3
f)2x-5/3-1=10,2+x prosze o pomoc potrzebuje jeszcz dzisaj potrzebuje tego zadnia !!!!!!!

Answer 1

a)2x+5=14,8+(x-3)

2x+5=14,8+x-3

2x-x=14,8-3-5

x=6,8

b)1/4x-(4+1/2x)=-2

1/4x-4-1/2x=-2

1/4x-1/2x=-2+4

1/4x-2/4x=2

-1/4x=2 |: (-1/4) <-0,25>

x=0

c)2(3-x)-4(x-5)=2x+2

6-2x-4x+20=2x+2

-2x-4x-2x=2-6-20

-8x=-24 |: (-8)

x=3

d)1/3(-6x+9)-4=-5(x+1)

-2x+3-4=-5x-5

3-4+5=-5x+2x

4=-3x |(-3)

x= -1,3(3)

e)0,2.(10-5x)=3+2(x-1)

2-1x=3+2x-2

-1x-2x=1-2

-3x=-1 |:(-3)

x=-1/3=0,3(3)

f)37=(20-4x)*0,5-7x

37=20-4x*0,5-7x

37=20-2x-7x

37-20=-2x-7x

17=-9x |:(-9)

x~1,9

 

 

Answer 2

a) 2x+5=14,8+x-3

    x= 14,8-3-5

    x= 6,8

 

b) 1/4 x - 4 - 1/2x = -2

    1/4 x - 2/4 x = -2 + 4

    -1/4x = 2    |* (-1/4) 

     x=  - 1/2

 

c)  2,5x - 2/2= 8x+0,5/7

     2,5x - 8x = 0,5/7 + 2/2

     -5,5x = 1/14 + 14/14

     -5,5x = 15/14   |: (-5,5)

      x= 15/77

 

d)   x-5/8 = 5x -18/12

      x-5x = -18/12 + 5/8

      - 4x = -32/24 + 15/24

      -4x = -17/24     |: (-4)

      x = 17/96

 

e)   4/x-2 = 5/12x-1 1/3

      4/x - 5/12x= -1 1/3  - 2

      43/12x = -2 1/3   |: 43/12

      x= 28/43

 

f)  2x-5/3-1=10,2+x

     2x - x= 10,2 +5/3 +1

     x= 11 13/15