Tap the blue circles to see an explanation.
$$ \begin{aligned}(3x-1)(x+5)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}3x^2+15x-x-5 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}3x^2+14x-5\end{aligned} $$ | |
① | Multiply each term of $ \left( \color{blue}{3x-1}\right) $ by each term in $ \left( x+5\right) $. $$ \left( \color{blue}{3x-1}\right) \cdot \left( x+5\right) = 3x^2+15x-x-5 $$ |
② | Combine like terms: $$ 3x^2+ \color{blue}{15x} \color{blue}{-x} -5 = 3x^2+ \color{blue}{14x} -5 $$ |