Respostas

2014-06-03T17:10:13-03:00
X² + 10x +9=0 
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-10 +/- v100 - 26 /2
-10 +/- v64/2

x'= -10 +8 /2
x'= -1

x"= -10 -8 /2
x"= -9

Resposta -1 ou -9
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