Prove limit of f(x)=x+a using epsilon-delta definition

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I am trying to prove that $\lim_{x \to 0}(x+a)=a $, using the epsilon delta definition of limits. Here is my attempt:

Let $0<\left | x \right |<\delta $ and $\left | x+a \right |<\varepsilon$ for $\varepsilon>0$

By triangle inequality:

$\left | x+a \right |\leq \left | x \right |+\left | a \right |<\delta +\left | a \right |<\varepsilon\\\\\Rightarrow \delta < \varepsilon-\left | a \right |$

But this is not true for $\varepsilon \leq \left | a \right |$, since that would give a $\delta < 0$.

Any help would be appreciated.

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You have to show:

if $ \epsilon >0$ is given, then there exists $ \delta >0$ such that

$$|f(x)-a| < \epsilon$$

if $0< |x|< \delta.$

Hint: we have $|f(x)-a|=|x|.$