Question

determine o zero ou raiz da função

y=x²-8x-9​

Answer 1

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x² - 8x - 9

x = -b ± √b² - 4ac

2a

x = -(-8) ± √(-8)² - 4(1)(-9)

2(1)

x = 8 ± √64 + 36

2

x = 8 ± √100

2

x = 8 ± 10

2

x = 4 ± 5

x' = 9

x" = -1

S = { 9 ; -1 }

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Att: MarcosPCV