Question
Answer
$$(7x-9)\cdot(4-x)(-5x)=35x^3-185x^2+180x$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(7x-9)\cdot(4-x)(-5x)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}(28x-7x^2-36+9x)(-5x) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}(-7x^2+37x-36)(-5x) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}35x^3-185x^2+180x\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{7x-9}\right) $ by each term in $ \left( 4-x\right) $. $$ \left( \color{blue}{7x-9}\right) \cdot \left( 4-x\right) = 28x-7x^2-36+9x $$ |
| ② | Combine like terms: $$ \color{blue}{28x} -7x^2-36+ \color{blue}{9x} = -7x^2+ \color{blue}{37x} -36 $$ |
| ③ | $$ \left( \color{blue}{-7x^2+37x-36}\right) \cdot -5x = 35x^3-185x^2+180x $$ |
This page was created using
Simplify polynomials calculator