| $$ \begin{aligned}\frac{10x^2-60x}{50}x^2& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{10x^4-60x^3}{50}\end{aligned} $$ | |
| ① | Multiply $ \dfrac{10x^2-60x}{50} $ by $ x^2 $ to get $ \dfrac{ 10x^4-60x^3 }{ 50 } $. Step 1: Write $ x^2 $ as a fraction by putting $ \color{red}{ 1 } $ in the denominator. Step 2: Multiply numerators and denominators. Step 3: Simplify numerator and denominator. $$ \begin{aligned} \frac{10x^2-60x}{50} \cdot x^2 & \xlongequal{\text{Step 1}} \frac{10x^2-60x}{50} \cdot \frac{x^2}{\color{red}{1}} \xlongequal{\text{Step 2}} \frac{ \left( 10x^2-60x \right) \cdot x^2 }{ 50 \cdot 1 } = \\[1ex] & \xlongequal{\text{Step 3}} \frac{ 10x^4-60x^3 }{ 50 } \end{aligned} $$ |