bonjour, aidez moi svp: devellopper et réduire: A=(a-12+b)-(-12-a+b)+(b+1) B=9-(x-3+y)+(x-7) C=3(2+a)-(6-3a)+4(1-2a) D=(2a+3)(1-3a)+3(3+2a) E=5-(4-(3a-5)+(a+5))

A=(a-12+b)-(-12-a+b)+(b+1)
A= a -12 +b +12 +a -b +b +1
A= 2a +b +1

B=9-(x-3+y)+(x-7)
B= 9 - x +3 -y +x -7
B= -y +5

C=3(2+a)-(6-3a)+4(1-2a)
C= 6 +3a -6 +3a +4 -8a
C=-2a +4

D=(2a+3)(1-3a)+3(3+2a)
D= 2a -6a² +3 -9a +9 +6a
D= -6a² - a +12

E=5-(4-(3a-5)+(a+5))
E= 5 - ( 4 -3a +5 +a +5)
E= 5- 4 +3a -5 -a -5
E= 2a -9

A=(a-12+b)-(-12-a+b)+(b+1)
A = a-12+b+12+a-b+b+1
A = 2a+b+1

B=9-(x-3+y)+(x-7)
B = 9-x+3-y+x-7
B = 5-y

C=3(2+a)-(6-3a)+4(1-2a)
C = 6+3a-6+a+4-8a
C = 16 -4a

D=(2a+3)(1-3a)+3(3+2a)
D = 2a-6a²+3-9a+9+6a
D = 12-a-6a²

E=5-(4-(3a-5)+(a+5))
E = 5-4+3a+5-a-5
E = 2a+1