Example2.4.2A Solution

Consider the equation $$y+2=3\text{,}$$ which has only one variable, $$y\text{.}$$ If we substitute in $$1$$ for $$y$$ and then simplify:

\begin{align*} y+2\amp=3\\ \substitute{1}+2\amp\stackrel{?}{=}3\\ 3\amp\stackrel{\checkmark}{=}3 \end{align*}

we get a true equation. So we say that $$1$$ is a solution to $$y+2=3\text{.}$$ Notice that we used a question mark at first because we are unsure if the equation is true or false until the end.

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