Question
Answer
$$2(x-2)^2-x=2x^2-9x+8$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}2(x-2)^2-x& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}2(x^2-4x+4)-x \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}2x^2-8x+8-x \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}2x^2-9x+8\end{aligned} $$ | |
| ① | Find $ \left(x-2\right)^2 $ using formula. $$ (A - B)^2 = \color{blue}{A^2} - 2 \cdot A \cdot B + \color{red}{B^2} $$where $ A = \color{blue}{ x } $ and $ B = \color{red}{ 2 }$. $$ \begin{aligned}\left(x-2\right)^2 = \color{blue}{x^2} -2 \cdot x \cdot 2 + \color{red}{2^2} = x^2-4x+4\end{aligned} $$ |
| ② | Multiply $ \color{blue}{2} $ by $ \left( x^2-4x+4\right) $ $$ \color{blue}{2} \cdot \left( x^2-4x+4\right) = 2x^2-8x+8 $$ |
| ③ | Combine like terms: $$ 2x^2 \color{blue}{-8x} +8 \color{blue}{-x} = 2x^2 \color{blue}{-9x} +8 $$ |
This page was created using
Simplify polynomials calculator