Предмет: Математика, автор: 6929305

Если при a=-4 и a=2 значения выражения:
5а³+2а²-аb+c=0, то чему равно b+c?

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Ответы

Автор ответа: iosiffinikov
1

Ответ:

120

Пошаговое объяснение:

5*(-64)+32+4b+c=0   ( a=-4)

5*8+2*4-2b+c=0          (a=2)

-320+32+4b+c=0

40+8-2b+c=0

Вычтем из второго первое:

360-24-6b=0

60--4=b

b=56

48-112=-с

с=64

b+с=120

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