###### Example2.4.3Not 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 $$x+4\gt 5\text{.}$$

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