###### Example4.10.7

Is the point $$(1,2)$$ a solution of $$y\gt2x+1\text{?}$$

In the inequality $$y\gt2x+1\text{,}$$ substitute $$x$$ with $$1$$ and $$y$$ with $$2\text{,}$$ and we will see whether the inequality is true:

\begin{align*} y\amp\gt2x+1\\ 2\amp\stackrel{?}{\gt}2(2)+1\\ 2\amp\stackrel{\text{no}}{\gt}5 \end{align*}

Since $$2\gt5$$ is not true, $$(1,2)$$ is not a solution of $$y\gt2x+1\text{.}$$

in-context