Qqn pourrai venir m'aider svp

1-
12 + (2x - 3)
= 12 + 2x - 3
= 2x + 9

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

3-
(3x - 5) + (4x + 2)
= 3x - 5 + 4x + 2
= 3x + 4x - 5 + 2
= 7x - 3

4-
- (2x + 3) - (3x - 4)
= - 2x - 3 - 3x + 4
= - 2x - 3x - 3 + 4
= - 5x + 1

5-
(x - 6) + 2x
= x - 6 + 2x
= x + 2x - 6
= 3x - 6

6-
12x + 3 (2 - 2x)
= 12x + 6 - 6x
= 12x - 6x + 6
= 18x + 6

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

8-
4x - 3 (5x + 2)
= 4x - 15x - 6
= - 11x - 6

9-
7 - 2x (x + 3) + 5 (4x + 2)
= 7 - 2x² - 6x + 20x + 10
= - 2x² - 6x + 20x + 10 + 7
= - 2x² + 14x + 17

10-
(2x + 3) (3x - 2)
= 6x² - 4x + 9x - 6
= 6x² + 5x - 6

11-
(x - 1) (2x + 3) + 2 (2x + 3)
= 2x² + 3x - 2x - 3 + 4x + 6
= 2x² + 3x + 4x - 2x - 3 + 6
= 2x² + 5x + 3

12-
2x - (3x + 4) (x - 1)
= 2x - (3x² - 3x + 4x - 4)
= 2x - 3x² + 3x - 4x + 4
= - 3x² + 2x + 3x - 4x + 4
= - 3x² + x + 4

13-
(3x - 4) (2x - 4)
= 6x² - 12x - 8x + 16
= 6x² - 20x + 16

14-
2/3 (3x - 9)
= 6/3x - 18/3
= 6x - 18

15-
(3/4x + 1/2) (4/3x - 4)
= 12/12x - 12/4x + 4/6x - 4/2
= 12/12x - 36/12x + 8/12x - 24/12
= 12x - 36x + 8x - 24
= - 16x - 24

16-
- 5 (x + 1) - (2x - 3) (2x + 3)
= - 5x + 1 - (4x² + 6x - 6x - 9)
= - 5x + 1 - 4x² - 6x + 6x + 9
= - 4x² - 5x + 1 + 9
= - 4x² - 5x + 10

17-
(x + 2) (x - 1) + 2 (x² + 3x - 1)
= x² - x + 2x - 2 + 2x² + 6x - 2
= x² + 2x² - x + 2x + 6x - 2 - 2
= 3x² + 7x - 4