Respostas

2014-02-17T19:06:16-03:00
X+x^2 = 20
X + x^2 -20 = 0

Delta = 1^ - 4.(-1).(-20)
Delta = 81

x = (-1 +/- raiz delta ) / 2 .(1)
X = (- 1 +/- 9) / 2

x = 4 ou x = - 5. Testando a resposta seria o 4, pois 4 + 16 = 20
1 5 1