Answer
$$4a^2-9-(a^3+2a-9)=-a^3+4a^2-2a$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}4a^2-9-(a^3+2a-9)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}4a^2-9-a^3-2a+9 \xlongequal{ } \\[1 em] & \xlongequal{ }4a^2 -\cancel{9}-a^3-2a+ \cancel{9} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-a^3+4a^2-2a\end{aligned} $$ | |
| ① | Remove the parentheses by changing the sign of each term within them. $$ - \left( a^3+2a-9 \right) = -a^3-2a+9 $$ |
| ② | Combine like terms: $$ 4a^2 \, \color{blue}{ -\cancel{9}} \,-a^3-2a+ \, \color{blue}{ \cancel{9}} \, = -a^3+4a^2-2a $$ |
This page was created using
Simplify polynomials calculator