| $$ \begin{aligned}\frac{6x^2+3x-45}{2x-5}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}3x+9\end{aligned} $$ | |
| ① | Simplify $ \dfrac{6x^2+3x-45}{2x-5} $ to $ 3x+9$. Factor both the denominator and the numerator, then cancel the common factor. $\color{blue}{2x-5}$. $$ \begin{aligned} \frac{6x^2+3x-45}{2x-5} & =\frac{ \left( 3x+9 \right) \cdot \color{blue}{ \left( 2x-5 \right) }}{ 1 \cdot \color{blue}{ \left( 2x-5 \right) }} = \\[1ex] &= \frac{3x+9}{1} =3x+9 \end{aligned} $$ |