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