Réponse :
Explications étape par étape
Bonsoir
2x + 5x + 30 = 18 + x
7x - x = 18 - 30
6x = -12
x = -12/6
x = -2
2x(5 - 3x) = -5x + 40 - 6x^2
10x - 6x^2 = -5x + 40 - 6x^2
6x^2 - 6x^2 + 10x + 5x = 40
15x = 40
x = 40/15
x = (8 * 5)/(3 * 5)
x = 8/3
3a + 2x - 5a = 10 - 5(8 + a) + 3a
-2a + 2x = 10 - 40 - 5a + 3a
2x = -30 - 2a + 2a
2x = -30
x = -30/2
x = -15
