Question

resolva as equações

3,5×+8=-2 (× +7)

5 (3-×)=2 (×-4)+15

3 (2×-1)=-2 (×+3)

3 (×-2)-5 (×-1)= -7

15+3 (×+2)=-7× +2 (×+1)
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Answer 1

a) 3,5x + 8 = -2 (x+7)

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

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

5,5x = -22

x = -22/5,5 (coloca a fração em números inteiros)

x = -44/11

x = 4

b) 5 (3-x) = 2 (x-4) + 15

15 - 5x = 2x - 8 + 15 (corta 15 dos dois lados)

-5x - 2x = -8

-7x = -8

x = 8/7

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

6x -3 = -2x + 6

6x + 2x = 6 + 3

8x = 9

x = 9/8

d) 3 (x-2) - 5 (x-1) = -7

3x - 6 - 5x - 5 = -7

3x - 5x = -7 + 6 + 5

-2x = -7 + 11

-2x = 4

x = -4/2

x = -2

e) 15 + 3 (x + 2) = -7x + 2 (x + 1)

15 + 3x + 6 = -7x + 2x + 2

3x + 7x - 2x = 2 - 15 - 6

10x - 2x = -13 - 6

8x = -19

x = -19/8

Answer 2

Oi....

Resolução.

a)

3,5x + 8 = - 2(x + 7)

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

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

5,5x = - 22 ⇒(- 1)

x = - 22/5,5

x = - 4

b)

5(3 - x) = 2(x - 4) + 15

15 - 5x = 2x - 8 + 15

- 5x = 2x - 8

- 5x - 2x = - 8

- 7x = - 8 ⇒(- 1)

7x = 8

x = 8/7

c)

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

6x - 3 = - 2x - 6

6x + 2x = - 6 + 3

8x = - 3

x = - 3/8

d)

3(x - 2) - 5(x - 1) = - 7

3x - 6 - 5x + 5 = - 7

- 2x - 1 = - 7

- 2x =  - 7 + 1

- 2x = - 6 ⇒( - 1)

2x = 6

x = 6/2

x = 3

e)

15 + 3(x + 2) = - 7x + 2(x + 1)

15 + 3x + 6 = - 7x + 2x + 2

21 + 3x = - 5x + 2

3x + 5x = 2 - 21

8x = - 19

x = - 19/8

Bons estudos.