bonjour,
A=-1+8-(-4)-(3-6x2)+1
A=-1+8-(-4)-(3-(6x2))+1
A=-1+8-(-4)-(3-12)+1
A=-1+8+4-3+12+1
A=8+4+12+1-1-3
A=25-4
A=21
B=3x5/10x20-45
B=(3x5)/10x20-45
B=15/10x20-45
B= (15/10)x20-45
B=1.5x20-45
B= 30-45
B=-15
C= (5x8-3+24/3)/(8²+5x11)
C=(5x8)-3+24/3)/8²+(5x11)
C=40+3+8/8²+55
C= 51/64+55
C=51/109