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bonjour
A = ( x + 7 ) ( 2 x - 5 ) - ( 2 x - 5 ) ( 3 x + 2)
A = ( 2 x - 5 ) ( x + 7 - 3 x - 2)
A = ( 2 x - 5 ) ( - 2 x + 5 )
B = ( 4 x - 3 ) ( 2 x + 1 ) - 5 x ( 4 x - 3 )
B = ( 4 x - 3 ) ( 2 x + 1 - 5 x )
B = ( 4 x - 3 ) ( - 3 x + 1 )
C = ( 2 x - 5 ) ( x + 2) - ( 2 x - 5 ) ( 3 x - 7 )
C = ( 2 x - 5 ) ( x + 2 - 3 x + 7 )
C = ( 2 x - 5 ) ( - 2 x + 9 )