Предмет: Алгебра, автор: angelpan79

Число -7 є коренем рівняння х²-17х+c=0 Знайдіть значення с і
другий корінь рівняння.

Ответы

Автор ответа: prettypushkova
5

х² - 17х + с = 0

х₁ = -7

(-7)² - 17 · (-7) + с = 0

49 + 119 + с = 0

с = - 49 - 119

с = -168

- - - - - - - - - - - - -

D = b² - 4ac = (-17)² - 4 · 1 · (-168) = 289 + 672 = 961

√D = √961 = 31

х₁ = (17-31)/(2·1) = (-14)/2 = -7

х₂ = (17+31)/(2·1) = 48/2 = 24

Вiдповiдь: с = -168; х₂ = 24.

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