A linear equation has an unknown to the power 1, like $x + 5 = 12$. To solve, do the same operation to both sides until $x$ is alone.
Example: $2x + 3 = 11 \;\Rightarrow\; 2x = 8 \;\Rightarrow\; x = 4$.
Remember
- Whatever you do to one side, do to the other.
- Undo $+$ with $-$, and $\times$ with $\div$.