bonjour, pour résoudre ce calcul

Bonjour,

A = - 10/63 x - 7/25
A = - 10/63 x 7/25
A = - 70/1575
A = 35 x - 2 / 35 x 45
A = - 2/45

B = 9/20 + 43/60
B = 9 x 3 / 20 x 3 + 43/60
B = 27/60 + 43/60
B = 70/60
B = 10 x 7 / 10 x 6
B = 7/6

C = 77/30 x - 25/22
C = - 1925/660
C = 55 x - 35 / 55 x 12
C = - 35/12

D = - 7/6 - - 2/3
D = - 7/6 + 2/3
D = - 7/6 + 2 x 2 / 3 x 2
D = - 7/6 + 4/6
D = - 3/6
D = 3 x - 1 / 3 x 2
D = - 1/2

E = 7/3 x (3/4 - 9/2)
E = 7/3 x (3/4 - 9 x 2 / 2 x 2)
E = 7/3 x (3/4 - 18/4)
E = 7/3 x - 15/4
E = - 105/12
E = 3 x - 35 / 3 x 4
E = - 35/4

F = - 5/12 - 8/15 x 40/16
F = - 5/12 - 320/240
F = - 5 x 20 / 12 x 20 - 320/240
F = - 100/240 - 320/240
F = - 420/240
F = 60 x - 7 / 60 x 4
F = - 7/4

G = 1/3 - 4/3 x 5/2
G = 1/3 - 20/6
G = 1 x 2 / 3 x 2 - 20/6
G = 2/6 - 20/6
G = - 18/6
G = 6 x - 3 / 6 x 1
G = - 3

H = - 7/12 - 8/15 x 5/4
H = - 7/12 - 40/60
H = - 7 x 5 / 12 x 5 - 40/60
H = - 35/60 - 40/60
H = - 75/60
H = 15 x - 5 / 15 x 4
H = - 5/4

I = 2 - (1/8 - 3/8 x 4/5)
I = 2 - (1/8 - 12/40)
I = 2 x 40 / 1 x 40 - (1 x 5 / 8 x 5 - 12/40)
I = 80/40 - (5/40 - 12/40)
I = 80/40 - (- 7/40)
I = 80/40 + 7/40
I = 87/40

J = (5 + 3/4) x (10/9 x 18/25)
J = (5 x 4 / 1 x 4 + 3/4) x (180/225)
J = (20/4 + 3/4) x 180/225
J = 23/4 x 180/225
J = 4140/900
J = 180 x 3 / 180 x 5
J = 3/5