Question
Answer
$$(2a+5b)(2a-5b)=4a^2-25b^2$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(2a+5b)(2a-5b)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}4a^2-10ab+10ab-25b^2 \xlongequal{ } \\[1 em] & \xlongequal{ }4a^2 -\cancel{10ab}+ \cancel{10ab}-25b^2 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}4a^2-25b^2\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{2a+5b}\right) $ by each term in $ \left( 2a-5b\right) $. $$ \left( \color{blue}{2a+5b}\right) \cdot \left( 2a-5b\right) = 4a^2 -\cancel{10ab}+ \cancel{10ab}-25b^2 $$ |
| ② | Combine like terms: $$ 4a^2 \, \color{blue}{ -\cancel{10ab}} \,+ \, \color{blue}{ \cancel{10ab}} \,-25b^2 = 4a^2-25b^2 $$ |
This page was created using
Simplify polynomials calculator