Question

Resolva as equações e encontre a solução:

a) x + 5 = 12
b) 2x – 4 = 18
c) -8 + 3x = -14
d) 4x – 7 = 2x – 8
e) 6x – 4 = 12 – 9x
f) x + 4 – 3x = 4 + 12x
g) –5 + 3x + 4 = 11 + 9x

Answer 1

Resposta:

A) 4x - 7 = 2x - 8

4x - 2x -7 = - 8

4x - 2x = - 8 + 7

2x = - 8 + 7

2x = - 1

x = - \frac{1}{2}

2

1

B) 6x - 4 = 12 - 9x

6x + 9x - 4 = 12

6x + 9x = 12 + 4

15x = 12 + 4

15x = 16

x = \frac{16}{15}

15

16

C) x + 4 - 3x = 4 + 12x

x - 3x = 12x

- 2x = 12x

-2x - 12x = 0

- 14x = 0

x = 0

D) 3 + 4x - 9 = 6x - 4 + 12

-6 + 4x = 6x - 4 + 12

-6 + 4x = 6x + 8

-6 + 4x - 6x = 8

4x - 6x = 8 + 6

-2x = 8 + 6

-2x = 14

x = - 7

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

- 1 + 3x = 11 + 9x

-1 + 3x -9x = 11

3x - 9x = 11 + 1

-6x = 11 + 1

-6x = 12

x = -2