Bonsoir
a. 13 + (x - 6)
= 13 + x - 6
= x + 7
b. -5 - (4 - 2x)
= -5 - 4 + 2x
= 2x - 9
c. 10 - (x + 3) + (-3x + 6)
= 10 - x - 3 - 3x + 6
= -4x + 13
d. (5 + 2x) - ( -7 - 7x)
= 5 + 2x + 7 + 7x
= 9x + 12
e. x - 8 - (2 + 4x - (9 - 5x))
= x - 8 - (2 + 4x - 9 + 5x)
= x - 8 - 2 - 4x + 9 - 5x
= -8x - 1
Voilà j'espère avoir pu t'aider ^^