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quelqu'un peux m'aider svp ,meme un lien pour aider svp
Résoudre les équations suivantes en supprimant d’abord les parenthèses :
• 5 − (x − 3) = 4x − (3x − 8)
• 2 + x − (5 + 2x) − 7 = 3x + 7
• 4x + 3 − (x + 1) + 5 = 5x + 7
• 2x + 1 − (2 + x) − 7 = 3x + 7
• 5(x − 1) + 3(2 − x) = 0
• 7(x + 4) − 3(x + 2) = x + 7
• 2(x − 1) − 3(x + 1) = 4(x − 2)


Répondre :

Bonjour

5 − (x − 3) = 4x − (3x − 8)
<=> 5 - x + 3 = 4x - 3x + 8
<=> 8 - x = x + 8
<=> -x - x = 8 - 8
<=> -2x = 0
<=> x = 0

2 + x − (5 + 2x) − 7 = 3x + 7
<=> 2 + x - 5 - 2x - 7 = 3x + 7
<=> -10 - x = 3x + 7
<=> -x - 3x = 7 + 10
<=> -4x = 17
<=> x = -17/4

4x + 3 − (x + 1) + 5 = 5x + 7
<=> 4x + 3 - x - 1 + 5 = 5x + 7
<=> 3x + 7 = 5x + 7
<=> 3x - 5x = 7 - 7
<=> -2x = 0
<=> x = 0

2x + 1 − (2 + x) − 7 = 3x + 7
<=> 2x + 1 - 2 - x - 7 = 3x + 7
<=> x - 8 = 3x + 7
<=> x - 3x = 7 + 8
<=> -2x = 15
<=> x = -15/2

5(x − 1) + 3(2 − x) = 0
<=> 5x - 5 + 6 - 3x = 0
<=> 2x + 1 = 0
<=> 2x = -1
<=> x = -1/2

7(x + 4) − 3(x + 2) = x + 7
<=> 7x + 28 - 3x - 6 = x + 7
<=> 7x + 28 - 3x - 6 - x - 7 = 0
<=> 3x + 15 = 0
<=> 3x = -15
<=> x = -15/3
<=> x = -5

2(x − 1) − 3(x + 1) = 4(x − 2)
<=> 2x - 2 - 3x - 3 = 4x - 8
<=> 2x - 2 - 3x - 3 - 4x + 8 = 0
<=> -5x + 3 = 0
<=> -5x = -3
<=> x = 3/5

Voilà j'espère avoir pu t'aider ^^