Question

va rog sa ma ajutati...urgent​

Answer 1

Răspuns:

Explicație pas cu pas:

ex 10 :

a) 2(5x - 2) < 7x - 16

10x - 4 < 7x - 16

10x - 7x < - 16 + 4

3x < - 12

x < - 12 : 3 → x < - 4

b) 3(2x + 7) > 8x + 11

6x + 21 > 8x + 11

6x - 8x > 11 - 21

- 2x > - 10

x < 10 : 2 → x < 5

c) 5(6 - 3x) ≤ 12 - 9x

30 - 15x ≤ 12 - 9x

- 15x + 9x ≤ 12 - 30

- 6x ≤ - 18

x ≥ 18 : 6 → x ≥ 3

d) 4(5 - 2x) ≥ 40 - 3x

20 - 8x ≥ 40 - 3x

- 8x + 3x ≥ 40 - 20

- 5x > 20

x ≤ 20 : (- 5) → x ≤ - 4

e) 24 - 3x < 6(10 + x)

24 - 3x < 60 + 6x

- 3x - 6x < 60 - 24

- 9x < 36

x > 36 : (- 9) → x > - 4

f) 75 - 15x > 8(5 - x)

75 - 15x > 40 - 8x

- 15x + 8x > 40 - 75

- 7x > - 35

x < 35 : 7 → x < 5

ex 11 :

a) 3(2x - 5) < 5(4x + 1) + 22

6x - 15 < 20x + 5 + 22

6x - 15 < 20x + 27

6x - 20x < 27 + 15

- 14x < 42

x > 42 : (- 14) → x > - 3

b) 2(3x + 7) + 19 > 3(6x - 1)

6x + 14 + 19 > 18x - 3

6x + 33 > 18x - 3

6x - 18x > - 3 - 33

- 12x > - 36

x < 36 : 12 → x < 3

c) 29 - 4(x + 15) ≤ 3(3 + 2x)

29 - 4x - 60 ≤ 9 + 6x

- 31 - 4x ≤ 9 + 6x

- 4x - 6x ≤ 9 + 31

- 10x ≤ 40

x ≥ 40 : (- 10) → x ≥ - 4

d) 30 - 5(x + 14) ≥ 2(2x + 7)

30 - 5x - 70 ≥ 4x + 14

- 40 - 5x ≥ 4x + 14

- 5x - 4x ≥ 14 + 40

- 9x ≥ 54

x ≤ 54 : (- 9) → x ≤ - 6