Respostas

  • Usuário do Brainly
2014-05-26T17:14:21-03:00


a)   y²+10y+25=81

y²+10x-56=0

Δ=100+224=324

y=(-10+18)/2= 8/2=4

y=(-10-18)/2=-28/2=-14                       S={-14,4}



b)  x²+4x+4=100

x²+4x-96=0

Δ=16+384=400

x=(-4+20)/2=16/2=8

x=(-4-20)/2=-24/2=-12             S={-12,8}

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