$$ \begin{aligned}\frac{1-9w^2}{12w-4}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{-3w-1}{4}\end{aligned} $$ | |
① | Factor both the denominator and the numerator, then cancel the common factor. $\color{blue}{3w-1}$. $$ \begin{aligned} \frac{1-9w^2}{12w-4} & =\frac{ \left( -3w-1 \right) \cdot \color{blue}{ \left( 3w-1 \right) }}{ 4 \cdot \color{blue}{ \left( 3w-1 \right) }} = \\[1ex] &= \frac{-3w-1}{4} \end{aligned} $$ |