Bonjour,
Calculer sous forme fractionnaire :
A = -20/12-2/3
A = (4 x - 5) / (4 x 3) - 2/3
A = - 5/3 - 2/3
A = - 7/3
B= -5/20+9/-6
B = (5 x - 1) / (5 x 4) - (3 x 3) / (3 x 2)
B = - 1/4 - 3/2
B = - 1/4 - (3 x 2) / (2 x 2)
B = - 1/4 - 6/4
B = - 7/4
C = 7/9-56/12
C = (7 x 4) / (9 x 4) - (56 x 3) / (12 x 3)
C = 28/36 - 168/36
C = - 140/36
C = (4 x - 35) / (4 x 9)
C = - 35/9
D= 18/24+9/36
D = (6 x 3) / (6 x 4) + (9 x 1) / (9 x 4)
D = 3/4 + 1/4
D = 4/4
D = 1.