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