Répondre :
Bonjour;
A = 15x- (8x+2)+(3x-5)
= 15x -8x -2 +3x -5
=10x -7
B=8x²-6-(5x-9)+7x²-(x²-3x)-11
= 8x² -6 -5x +9 +7x² -x² +3x -11
= 14x² -2x -8
Bonjour,
A = 15x - (8x + 2) + (3x - 5)
= 15x - 8x - 2 + 3x - 5
= 10x - 7
B = 8x² - 6 - (5x - 9) + 7x² - (x² - 3x) - 11
= 8x² - 6 - 5x + 9 + 7x² - x² + 3x - 11
= 14x²-2x - 8