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2014-05-16T14:29:33-03:00
a) \\ \\   \frac{1x^2}{4} + \frac{5x}{4} -6=0 \\  \\ x^2+5x-24=0 \\   \\ \\ D=b^2-4.a.c \\   \\ \\ D=5^2-4.1.(-24) \\  \\ D=25+96 \\  \\ D=121

 \frac{-b+/- \sqrt{D} }{2}  \\  \\ x'= \frac{-5+11}{2} \>\>\>\>\>\>\>x'= \frac{6}{2} \>\>\>\>\>\>\>x'=3 \\  \\ x"=\frac{-5-11}{2}\>\>\>\>\>\>\>x"= \frac{-16}{2} \>\>\>\>\>\>\>x"=-8
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b)\\ \\x^2+5x-2=-8 \\  \\ x^2+5x-2+8=0 \\  \\ x^2+5x+6=0 \\   \\ \\ D=b^2-4.a.c \\  \\  \\ D=5^2-4.1.6 \\  \\ D=25-24 \\  \\ D=1

 \frac{-b+/- \sqrt{D} }{2.a}  \\  \\ x'=\frac{-5+1}{2}\>\>\>\>\>\>\>x'= \frac{-4}{2}\>\>\>\>\>\>\>x'=-2 \\  \\ x"= \frac{-5-1}{2}  \>\>\>\>\>\>\>x"= \frac{-6}{2} \>\>\>\>\>\>\>x"=-3

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