Respostas

2013-10-22T13:00:46-02:00
-x²= - 7x - 12
∆ = b² - 4 a c
∆ = (-7)² - 4 . 1 . 12
∆ = 49 - 48
∆ = 1
x =(-b ± √ ∆ ) / 2a
x =( 7 ± √ 1 ) / 2 . 1

x¹ = ( 7 + 1 ) / 2
x¹ = 8 / 2
x¹ = 4

x²= ( 7 - 1 ) / 2
x²= 6 / 2
x²= 3


Resposta: x¹ = 4 x² = 3
1 4 1