Verified answer

Resposta passo a passo:

1 -

a) 3 . (x + 2) = 2 . (x - 7)

3x + 6 = 2x - 14

3x - 2x = -6 - 14

x = -(6 + 14)

x = -20

b) 3 . (x + 2) - 1 = 2 . (x + 3) - 7

3x + 6 - 1 = 2x + 6 - 7

3x - 1 = 2x - 7

3x - 2x = -7 + 1

x = -(7 - 1)

x = -6

c) 3 . (x + 1) + 2 = 5 + 2 . (x - 1)

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

3x + 5 = 5 + 2x - 2

3x = 2x - 2

3x - 2x = -2

x = -2

d) 5 . (2x + 7) - 1 = 4 . (x - 5) + 9

10x + 35 - 1 = 4x - 20 + 9

10x + 35 = 4x - 20 + 9 + 1

10x + 35 = 4x - 20 + 10

10x + 35 + 20 = 4x + 10

10x + 55 = 4x + 10

10x + 55 - 10 = 4x

10x + 45 = 4x

10x - 4x = -45

6x = -45

x = -45/6 ← Simplificando para fração irredutível. (Dividindo ambos por 3).

x = -15/2

e) 2 . (x + 1) + 3 . (x + 1) = 4 . (x + 2)

5 . (x + 1) = 4 . (x + 2)

5x + 5 = 4x + 8

5x - 4x = 8 - 5

x = 3

f ) 2 . (x + 1) + 5 . (x - 1) = 7

2x + 2 + 5x - 5 = 7

2x + 5x - 5 = 7 - 2

7x - 5 = 5

7x = 5 + 5

7x = 10

x = 10/7

g) 2 . (2x + 3) + 5 . (x + 1) = 8 - (3x - 1)

4x + 6 + 5x + 5 = 8 - 3x + 1

4x + 5x + 11 = 9 - 3x

9x + 11 = 9 - 3x

9x + 3x = -11 + 9

12x = -(11 - 9)

12x = -2

x = -2/12

x = -1/6