Evaluate the following limit: `lim_(x->oo)sqrt(x^2+7x)-x`

Explanation

To evaluate the limit \( \lim_{x \to \infty} \left( \sqrt{x^2 + 7x} - x \right) \), we can follow these steps:

### Step 1: Rewrite the limit expression
We start with the limit:
\[ L = \lim_{x \to \infty} \left( \sqrt{x^2 + 7x} - x \right) \]

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