| $$ \begin{aligned}\frac{x^2-6x+8}{x^2-7x+12}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{x-2}{x-3}\end{aligned} $$ | |
| ① | Simplify $ \dfrac{x^2-6x+8}{x^2-7x+12} $ to $ \dfrac{x-2}{x-3} $. Factor both the denominator and the numerator, then cancel the common factor. $\color{blue}{x-4}$. $$ \begin{aligned} \frac{x^2-6x+8}{x^2-7x+12} & =\frac{ \left( x-2 \right) \cdot \color{blue}{ \left( x-4 \right) }}{ \left( x-3 \right) \cdot \color{blue}{ \left( x-4 \right) }} = \\[1ex] &= \frac{x-2}{x-3} \end{aligned} $$ |