Let $f(x) = x^2 + bx + 9$ and $g(x) = x^2 + dx + e.$  If $f(x) = 0$ has roots $r$ and $s,$ and $g(x) = 0$ has roots $-r$ and $-s,$ compute the two roots of $f(x) + g(x) = 0.$
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<|im_start|>user
Let $f(x) = x^2 + bx + 9$ and $g(x) = x^2 + dx + e.$  If $f(x) = 0$ has roots $r$ and $s,$ and $g(x) = 0$ has roots $-r$ and $-s,$ compute the two roots of $f(x) + g(x) = 0.$
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user
3i,-3i
Let $f(x) = x^2 + bx + 9$ and $g(x) = x^2 + dx + e.$  If $f(x) = 0$ has roots $r$ and $s,$ and $g(x) = 0$ has roots $-r$ and $-s,$ compute the two roots of $f(x) + g(x) = 0.$
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