Respostas

2014-05-12T16:38:11-03:00
X²+9X+8=0
A=1; B=9; C=8

Δ=b²-4ac
Δ=9²-4.1.8
Δ= 81-32
Δ=49

X= -b+/-√Δ/2a
X= -9+/-√49/2.1
X'= -9+7/2⇒ -9+7/2⇒-2/2=-1
X''= -9-7/2⇒-16/2=-8

Xv= -b/2a
Xv= -9/2.1
Xv= -9/2
Xv=  -4,5

Yv= -Δ/4a
Yv= -49/4.1
Yv= -12,25