bonjour
[tex]A ( x) = 9 x^{2} - 30 x + 25 + 2 x^{2} + 12 x \\A ( x ) = 11 x^{2} + 18 x + 25 \\\\B = 6 x^{2} - 16 x + 3 x - 8 - ( x^{2} + 8 x + 16 ) \\B = 6 x^{2} - 13 x - 8 - x^{2} - 8 x - 16 \\B = 5 x^{2} - 21 x - 24 \\\\C = x^{2} - 25 + x^{2} + 10 x + 25 \\C = 2 x^{2} + 10 x \\\\D = 4 x^{2} + 32 x + 64 - ( x^{2} + 2 x + x + 2 ) \\D = 4 x^{2} + 32 x + 64 - x^{2} - 3 x - 2 \\D = 3 x^{2} + 29 x + 62 \\\\\\[/tex]
