Réponse :
Explications étape par étape
Bsr,
1. (2x + 1)(4x - 1) = 0
2 solutions
2x+1 = 0
2x=-1
x = -1/2
ou
4x-1=0
4x= 1
x=1/4
2. (2x - 9)(-x - 2) = 0
2x-9 = 0
2x= 9
x= 9/2
ou
-x-2=0
-x = 2
x= -2
3. (3x - 5)(8 - 2x) = 0
3x-5 = 0
3x = 5
x= 5/3
ou
8-2x= 0
8 = 2x
x = 8/2 =4
4. (10 - 4x) * 7 = 0
10-4x = 0
10 = 4x
x= 4/10 = 1/5
5. 3x * (x - 1) = 0
3x=0
x=0
ou
x-1=0
x=1
6. x² - 100 = 0
x² = 100
x = √100 = 10
7-25x² -9= 0
7-9 = 25x²
-2 = 25x²
-2/25 = x²
√-2/25 = x
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