Respostas

2014-01-05T12:45:40-02:00
x²+7x+10=0
a= 1 b=7 c=10

Δ= b²-4ac
Δ= (7)²-4·1·10
Δ= 49-40
Δ= 9

Encontrando as raízes:

x= -b +/- √Δ/2a
x= -7 +/-√9/2·1
x= -7+/-3/2

x'= -2
x''= -5

S:[-2,5]
Alternativa C