calcul (donne des étapes intermediaires)

A: 3+2x8-5
3+16-5
19-5
14

B: 6+7-2x4+1
6+7-8+1
13-8+1
5+1
6

C: 3+2x5+5-2+3
3+10+5-2+3
13+5-2+3
18-2+3
16-3
19

A=3+2×8-5 A = 3 + 16 - 5 
A = 19 - 5A= 14
B=6+7-2×4+1 B = 6 + 7 - 8 + 1B = 14 - 8B = 6
C=3+2×5+5-2×3 C = 3 + 10 + 5 - 6C = 18 - 6C = 12