Answer
$$(x+4)(x-5)=x^2-x-20$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(x+4)(x-5)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}x^2-5x+4x-20 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}x^2-x-20\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{x+4}\right) $ by each term in $ \left( x-5\right) $. $$ \left( \color{blue}{x+4}\right) \cdot \left( x-5\right) = x^2-5x+4x-20 $$ |
| ② | Combine like terms: $$ x^2 \color{blue}{-5x} + \color{blue}{4x} -20 = x^2 \color{blue}{-x} -20 $$ |
This page was created using
Complex Expression calculator