Respuesta :

Answer:  " x = 16 ;  - 4 " .
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Note:
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-16 , +4  = -12 .

-16 * 4 = -64
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(x - 16)(x + 4) = 0 ; 
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x = 16 ;  - 4 .
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x² -12x -64=0
D=b² - 4ac=144+4*64=400

x=(-b+/-√D)/2a

x=(12+/-20)/2
x1=32/2=16
x2=-8/2= -4