Respuesta :

x^2 - 8x - 9 = 0
x^2 - 8x = 9
(x - 4)^2 - 16 = 9
(x - 4)^2 = 25

x - 4  = +/- sqrt25  = +/- 5

x = 5 + 4, -5 + 4 

Solution set is {-1, 9}

Answer:

^2−8=9

^2−8+16=9+16

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