Question

resolva a equacao de 2;grau
porfavor rapidinho

Answer 1

5) 2x^2-8x+8=0
delta=b^2-4ac
delta=(-8)^2-4.2.8
delta=64-64
delta=0
x=-b-/+ raiz de delta/2a
x=-(-8)-0/2.2
x=8-0/4
x=8/4
x=2
S={2}
6) x^2-4x-5=0
delta=b^2-4ac
delta=(-4)^2-4.1.(-5)
delta=16+20
delta=36
x=-b-/+ raiz de delta/2a
x=-(-4)-6/2.1
x=4-6/2
x=-2/2
x=-1
x=-(-4)+6/2.1
x=4+6/2
x=10/2
x=5
S={-1, 5}
7) -x^2+x+12=0
delta=b^2-4ac
delta=1^2-4.(-1).12
delta=1+48
delta=49
x=-b-/+ raiz de delta/2a
x=-1-7/2.(-1)
x=-8/-2
x=4
x=-1+7/2.(-1)
x=6/-2
x=-3
S={4, -3}
8) -x^2+6x-5=0
delta=b^2-4ac
delta=6^2-4.(-1).(-5)
delta=36-20
delta=16
x=-b-/+ raiz de delta/2a
x=-6-4/2.(-1)
x=-10/-2
x=5
x=-6+4/2.(-1)
x=-2/-2
x=1
S={5, 1}
9) 6x^2+x-1=0
delta=b^2-4ac
delta=1^2-4.6.(-1)
delta=1+24
delta=25
x=-b-/+ raiz de delta/2a
x=-1-5/2.6
x=-6/12 (÷6)
x=-1/2
x=-1+5/2.6
x=4/12 (÷4)
x=1/3
10) 3x^2-7x+2=0
delta=b^2-4ac
delta=(-7)^2-4.3.2
delta=49-24
delta=25
x=-b-/+ raiz de delta/2a
x=-(-7)-5/2.3
x=7-5/6
x=2/6 (÷2)
x=1/3
x=-(-7)+5/2.3
x=7+5/6
x=12/6
x=2