resoudre 36-(x-6)²=0  et (10-x)(x-2)=0 developper et réduire (10-x)(x-2)

36 - (x - 6)² = 0

Cas 1.
6 = x - 6
x - 6 = 6
x = 6 + 6
x = 12

Cas 2.
6 = - (x - 6)
6 = - x + 6
x = 6 - 6
x = 0

S= {0 ; 12}
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(10 - x)(x - 2) = 0
10 - x = 0 ou x - 2 = 0
10 = x ou x = 2

S= {2 ; 10}
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(10 - x)(x - 2)
= 10x - 20 - x² + 2x
= - x² + 12x - 20

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