Réponse :
2 * 3x + 5 * 2x
= 6x + 10x
= 16x
3x * 2x + 4 * 2x * x
= 6x² + 8x * x
= 6x² + 8x²
= 14x²
5 * 4x + 2 * 3x
= 20x + 6x
= 26x
3x * x + 4x * 2x
= 3x² + 8x²
= 11x²
4 * 2 + 4 * x - 2 * x
= 8 + 4x - 2x
= 8 + 2x
7 * 4x + 4 – 3 * 2x + 5
= 28x + 4 - 6x + 5
= 28x - 6x + 4 +5
= 22x + 9
Bon courage ^-^