J'aimerai Savoir Si J'ai Bon A Quelque Calculs ?!

[minnellea]

BONJOUR,

est ce que ces expression a simplifier sont bonne ? svp

A)

(4-7x) + (5-3x)-3(3x-5)-(x-6)-5+3x

= 4-7x +5 + 3x – 9x-15 – x-8 -5+3x

B)

2(x-1) –(7+2x) –(2x -2) +3(x-1)

=2x-1 -7+2x-2x-2+3x-1

=5x-9

C)

[ (2a-(b-c)] –[-5a-(b-3c)] -[6a-(b+3c)]

=2ab+2ac+5ab+15ac -6a-b+3c

=1ab+10ac

D)

[ 2(ab+ac)-3a] -2[(a+8)+ac]

=2ab+2ac -3a -2a -16+ac

merci d'avance ...!

[Barbidoux]

Règle :

même signes +(+ ou -(- = +

Signes contraires +(- ou -(+=-

A=(4-7x) + (5-3x)-3(3x-5)-(x-6)-5+3x

= 4-7x +5 -3x – 9x+15 –x+6-5+3x=25-17*x

B=2(x-1) –(7+2x) –(2x -2) +3(x-1)

=2x-2 -7-2x-2x+2+3x-3=x-4

C=(2*a-(b-c))-(-5*a-(b-3c))-(6*a-(b+3c))=2*a-b+c+5*a+(b-3*c)-6*a+(b+3c)= =2*a-b+c+5*a+b-3*c-6*a+b+3c=a+b+c

D=(2*(a*b+a*c)-3*a) -2*((a+8)+a*c)=2*(a*b+a*c)-3*a -2*(a+8)-2*a*c=2*a*b+2*a*c-3*a -2*a-16-2*a*c=2*a*b-5*a -16