Explications étape par étape:
A = 81x carré - 126X + 49. = ( 9X - 7 ) au carré
B = 99 - 34X - 5X carré. = ( 11 - 5X ) ( x + 9 )
C = 4X carré - 9
D = 64X carré + 176X + 121. = ( 8X + 11 ) carré
E = 1 + 16X - 6X carré
F = - 4X carré - 10X - 3
G = 7t carré - 12t - 5
H = 18s carré + 24s - 41
I = 11X carré + 35X + 10