Question

7) Resolva as equações a seguir:
a) 3(2x + 3) – 4(x – 1) = 3
b) 3(5 – x) – 3(1 – 2x) = 42
c) 5(x – 3) – 4(x + 2) = 2 + 3(1 – 2x)
d) 3(x – 2) = 4(3 – x)
e) 13 + 4(2x – 1) = 5(x + 2)

Answer 1

Resposta:

a) 3(2x + 3) – 4(x – 1) = 3

6x + 9 - 4x + 4 = 3

2x + 13 = 3

2x = 3 - 13

2x = -10

x = -5

b) 3(5 – x) – 3(1 – 2x) = 42

15 - 3x - 3 + 6x = 42

12 + 3x = 42

3x = 42 - 12

3x = 30

x = 10

c) 5(x – 3) – 4(x + 2) = 2 + 3(1 – 2x)

5x -15 - 4x - 8 = 2 + 3 - 6x

x - 23 = 5 - 6x

x - 23 + 6x = 5

7x = 5 + 23

7x = 28

x = 4

d) 3(x – 2) = 4(3 – x)

3x - 6 = 12 - 4x

3x + 4x - 6 = 12

7x = 12 + 6

7x = 18

x = $\frac{18}{7}$

e) 13 + 4(2x – 1) = 5(x + 2)

13 + 8x - 4 = 5x + 10

9 + 8x = 5x + 10

8x = 5x + 10 - 9

8x = 5x + 1

8x - 5x = 1

3x = 1

x = $\frac{1}{3}$