Example 4.10.7

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