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