Réponse :
Explications étape par étape
Bonsoir
2x + 3 = 5
2x = 5 - 3
x = 2/2
x = 1
4x + 1 < 9
4x < 9 - 1
x < 8/4
x < 2
\\\\\\\\\\\\\\\\\[
-inf................2
8x - 2 = 2x + 10
8x - 2x = 10 + 2
6x = 12
x = 12/6
x = 2 oui
x + x + 450 + x + 900 = 2250
3x + 1350 = 2250
3x = 2250 - 1350
x = 900 €
