Tap the blue circles to see an explanation.
$$ \begin{aligned}31y\cdot1-70y\cdot2+2x+5& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}31y-140y+2x+5 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-109y+2x+5 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}2x-109y+5\end{aligned} $$ | |
① | $$ 70 y \cdot 2 = 140 y $$ |
② | Combine like terms: $$ \color{blue}{31y} \color{blue}{-140y} = \color{blue}{-109y} $$ |
③ | Combine like terms: $$ -109y+2x+5 = 2x-109y+5 $$ |