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> $$\displaystyle\lim\_{x\to 9^{-}}\frac{x^2 − 9x}{x^2 − 18x + 81}$$
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Now since the value of 9 is coming from the left side, I substituted 8.99 for x however, after doing so all my values after calculating them are negative on the top and bottom, Thus, why is the answer negative infinity?