Respostas

2014-04-05T21:12:33-03:00
Delta=b²-4.a.c
Delta= (-4)²-4.1.-140
Delta= 576
-b+-raiz de Delta/2a= -(-4)+raiz de 576/2a= 14

-b-raiz de delta/2a= -(-4)-raiz de 576/2a= -10
2014-04-05T21:22:00-03:00
x²-4x-140=0
Δ = b2 -4ac
Δ. = (-4)² - 4 * 1 * (-140)
Δ. = 16 + 560
Δ. = 576

Báskara X = 4+ou- raiz quadrada de delta 576 / 2*1
             X = 4 +ou- 24 / 2
             X'= 4 + 24 / 2 = 28 / 2 = 14  X"= 4-24/2 = -20/2 = -10

Solução {14, -10}

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