Question

dentre os numeros -2,0,1,7 quais deles sao raizes da equacao x2-8x-7=0?

Answer 1

$x^2-8x-7=0 b^2 - 4.a.c = Δ 64-28 = 36 x =( -b+- \sqrt{delta})/2a x = 8+-6/2 x = 7 ou x = 1$