Tap the blue circles to see an explanation.
$$ \begin{aligned}(2x+3)^2+8(3-x-(x+2(x-2)))& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}4x^2+12x+9+8(3-x-(x+2(x-2))) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}4x^2+12x+9+8(3-x-(x+2x-4)) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}4x^2+12x+9+8(3-x-(3x-4)) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}}4x^2+12x+9+8(3-x-3x+4) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle5}{\textcircled {5}} } }}}4x^2+12x+9+8(-4x+7) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle6}{\textcircled {6}} } }}}4x^2+12x+9-32x+56 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle7}{\textcircled {7}} } }}}4x^2-20x+65\end{aligned} $$ | |
① | Find $ \left(2x+3\right)^2 $ using formula. $$ (A + B)^2 = \color{blue}{A^2} + 2 \cdot A \cdot B + \color{red}{B^2} $$where $ A = \color{blue}{ 2x } $ and $ B = \color{red}{ 3 }$. $$ \begin{aligned}\left(2x+3\right)^2 = \color{blue}{\left( 2x \right)^2} +2 \cdot 2x \cdot 3 + \color{red}{3^2} = 4x^2+12x+9\end{aligned} $$ |
② | Multiply $ \color{blue}{2} $ by $ \left( x-2\right) $ $$ \color{blue}{2} \cdot \left( x-2\right) = 2x-4 $$ |
③ | Combine like terms: $$ \color{blue}{x} + \color{blue}{2x} -4 = \color{blue}{3x} -4 $$ |
④ | Remove the parentheses by changing the sign of each term within them. $$ - \left( 3x-4 \right) = -3x+4 $$ |
⑤ | Combine like terms: $$ \color{blue}{3} \color{red}{-x} \color{red}{-3x} + \color{blue}{4} = \color{red}{-4x} + \color{blue}{7} $$ |
⑥ | Multiply $ \color{blue}{8} $ by $ \left( -4x+7\right) $ $$ \color{blue}{8} \cdot \left( -4x+7\right) = -32x+56 $$ |
⑦ | Combine like terms: $$ 4x^2+ \color{blue}{12x} + \color{red}{9} \color{blue}{-32x} + \color{red}{56} = 4x^2 \color{blue}{-20x} + \color{red}{65} $$ |