x^2-16x-4=0
x^2-16x+64-64-4=0
(x-8)^2-68=0
(x-8-2√17)(x-8+2√17)=0
x=8+2√17或x=8-2√17t^2+2t-35=o呢?会追加赏分的~t^2+2t-35=0 (t+7)(t-5)=0 t=-7或t=5