Bonjour
A = - 10/9 x (1/10 - - 13/3)
A = - 10/9 x [(1 x 3) / (10 x 3) + (13 x 10) / (3 x 10)]
A = - 10/9 x (3/30 + 130/30)
A = - 10/9 x 133/30
A = - 1 330/270
A = (10 x - 133) / (10 x 27)
A = - 133/27
B = (- 8/9 + 1) / (3/4 - 9)
B = [- 8/9 + (1 x 9) / (1 x 9)] : [3/4 - (9 x 4) / (1 x 4)]
B = (- 8/9 + 9/9) : (3/4 - 36/4)
B = 1/9 : - 33/4
B = 1/9 x - 4/33
B = - 4/297
C = - 8/7 - - 1/28 : - 2/5
C = - 8/7 - - 1/28 x - 5/2
C = - 8/7 - 5/56
C = (- 8 x 8) / (7 x 8) - 5/56
C = - 64/56 - 5/56
C = - 69/56
