| $$ \begin{aligned}4x^2-3+7x^5+2x^3-5x^4& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}7x^5-5x^4+2x^3+4x^2-3\end{aligned} $$ | |
| ① | Combine like terms: $$ 7x^5-5x^4+2x^3+4x^2-3 = 7x^5-5x^4+2x^3+4x^2-3 $$ |