Question

Resolve as equações: a) 2. (x-2)+5. (2-x)=-3. (2x+2) b) 2. (1-x)+1=3. (x-3)-2x c) 5. (x+1)-3. (2x+1)=4. (5-x)

Answer 1

a) 2(x-2)+5(2-x)=-3(2x+2)
    2x-4+10-5x=-6x+2
    2x-5x+6x=-6+4-10
    3x=-12
    x=-12/3
    x=-4

b)2(1-x)+1=3(x-3)-2x
   2-2x+1=3x-9-2x
   -2x-3x+2x=-9-2-1
    -3x=-12
     x=-12/-3
     x=4 

c) 5(x+1)-3(2x+1)=4(5-x)
    5x+5-6x-3=20-4x
    5x-6x+4x=-5+3+20
    3x=18
    x=18/3
    x=6

Answer 2

a) 2. (x - 2)+5.(2-x) = - 3. (2x+2) 

2x - 4 + 10 - 5x = - 6x - 6

2x + 6x - 5x = - 6 - 10 + 4

8x - 5x = - 16 + 4

3x = - 12

x = - 12/3

x = - 4


S:[ - 4 ]

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b) 2.(1-x)+1= 3.(x-3) - 2x

2 - 2x + 1 = 3x - 9 - 2x

- 2x - 3x + 2x = - 9 - 1 - 2 

- 5x + 2x = - 12

- 3x = - 12 .(-1)

3x = 12

x = 12/3

x = 4


S:[ 4 ]


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c) 5.(x+1) -3.(2x+1)= 4.(5-x)

5x + 5  - 6x - 3 = 20 - 4x

5x + 4x - 6x = 20 + 3 - 5

9x - 6x = 23 - 5

3x = 18

x = 18/3

x = 6


S:[ 6 ]