Question

a) x²-7x+12=2 b)x²+x-12=-15 c)x²+9x+8=8 d)x²+10x+24=-1 por favor,resolução completa

Answer 1

x² - 7x + 12 = 2
x² - 7x + 12 - 2 = 0
x² - 7x + 10 = 0

Delta = b² - 4ac
Delta = 49 - 4(1)(10)
Delta = 49 - 40
Delta = 9

X = (-b +- raiz delta) / 2a
X = (7 +- 3) / 2
x' = 10/2 = 5
x" = 4/2 = 2

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x² + x - 12 = -15
x² + x - 12 + 15 = 0
x² + x + 3 = 0

Delta = b² - 4ac
Delta = 1 - 4(1)(3)
Delta = 1 - 12
Delta = -11

Não existe raiz negativa

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x² + 9x + 8 = 8
x² + 9x + 8 - 8 = 0
x² + 9x = 0

x² + 9x = 0
x(x + 9) = 0
x = 0
x + 9 =0
x = -9

Delta = b² - 4ac
Delta = 81 - 4(1)(0)
Delta = 81

X = (-b +- raiz delta) / 2a
X = (-9 +- 9) / 2
x' = 0/2 = 0
x" = -18/2 = -9

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x² + 10x + 24 = -1
x² + 10x + 24 + 1 = 0
x² + 10x + 25 = 0

Delta = b² - 4ac
Delta = 100 - 4(1)(25)
Delta = 100 - 100
Delta = 0

X = (-b +- raiz delta) / 2a
X = (-10 +- 0) / 2
x' = -10/2 = -5
x" = -10/2 = -5

BONS ESTUDOS!