Bonjour
A = - 2/21 x 14/5 - 8/5
A = - 28/105 - 8/5
A = - 28/105 - (8 x 21) / (5 x 21)
A = - 28/105 - 168/105
A = - 196/105
A = (7 x - 28) / (7 x 15)
A = - 28/15
C = 4/- 3 + - 7/6 x - 2/5
C = - 4/3 + 14/30
C = (- 4 x 10) / (3 x 10) + 14/30
C = - 40/30 + 14/30
C = - 26/30
C = (2 x - 13) / (2 x 15)
C = - 13/15
