Question

$\sqrt{12 - x } = - x$
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Answer 1

Ответ:

x₁ = - 4 ; x₂ = 3 .

Объяснение:

√( 12 - x ) = - x

( √( 12 - x ) )²=(-x)²

12 - x = x²

x² + x - 12 = 0

D = 1 + 48 = 49 = 7²

x₁ = ( - 1 - 7 ) / 2 = - 8 / 2 = - 4

x₂ = ( - 1 + 7 ) / 2 = 6 / 2 = 3