| $$ \begin{aligned}\frac{q^2-4}{q^2-4q+4}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{q+2}{q-2}\end{aligned} $$ | |
| ① | Simplify $ \dfrac{q^2-4}{q^2-4q+4} $ to $ \dfrac{q+2}{q-2} $. Factor both the denominator and the numerator, then cancel the common factor. $\color{blue}{q-2}$. $$ \begin{aligned} \frac{q^2-4}{q^2-4q+4} & =\frac{ \left( q+2 \right) \cdot \color{blue}{ \left( q-2 \right) }}{ \left( q-2 \right) \cdot \color{blue}{ \left( q-2 \right) }} = \\[1ex] &= \frac{q+2}{q-2} \end{aligned} $$ |