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Stella [2.4K]
3 years ago
8

O número -3 é a raíz da equação x² - 7x - 2c = 0. Nessas condições, determine o valor do coeficiente c: A) 7 B) -2 C) -3 D) 15 E

) NDA
Mathematics
1 answer:
Free_Kalibri [48]3 years ago
4 0

Responder:

c = 15

Explicação passo a passo:

se -3 é a solução para a expressão x² - 7x - 2c = 0, para obter c, vamos substituir x = -3 na equação (uma vez que é uma raiz)

x² - 7x - 2c = 0

(-3) ² - 7 (-3) - 2c = 0

9 + 21 - 2c = 0

30 - 2c = 0

30 = 2c

Trocar

2c = 30

c = 30/2

c = 15

Portanto, o valor de c é 15

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