###### Example 2.4.3 Not a Solution

Consider the inequality \(x+4\gt 5\text{,}\) which has only one variable, \(x\text{.}\) If we substitute in \(0\) for \(x\) and then simplify:

\begin{align*}
x+4\amp\gt 5\\
\substitute{0}+4\amp\stackrel{?}{\gt}5\\
4\amp\stackrel{\text{no}}{\gt}5
\end{align*}

we get a false equation. So we say that \(0\) is *not* a solution to \(x+4\gt 5\text{.}\)