Question

x²-x-12=0


x²-4×-5=0
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Answer 1

Resposta:

(4, -3); (5, -1).

Explicação passo a passo:

x² - x - 12 = 0

x = - (-1) ± √(-1)² - 4 . 1 . (-12)/2 . 1

x = 1 ± √1 +48/2

x = 1 ± √49/2

x = 1 ± 7/2

x' = 1 + 7/2

x' = 8/2

x' = 4.

x" = 1 - 7/2

x" = - 6/2

x" = - 3.

x² - 4x - 5 = 0

x = - (-4) ± √(-4)² - 4 . 1 . (-5)/2 . 1

x = 4 ± √16 + 20/2

x = 4 ± √36/2

x = 4 ± 6/2

x' = 4 + 6/2

x' = 10/2

x' = 5.

x" = 4 - 6/2

x" = - 2/2

x" = - 1.