Explications étape par étape:

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

5x-5 = 6x+4

5x-6x = 4+5

-x = 9

x= -9

b) 2 (3x+1) - 5 (6-x) = 2-x

6x+2-30+5x = 2-x

6x-30+5x = -x

11x-30 = -x

11x + x = 30

12x+30

Solution = x=5

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