$\left ( \color{#FF6800}{ 1 } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \right ) \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ 4 } \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ 3 } \right )$
$ $ Get rid of unnecessary parentheses $ $
$\color{#FF6800}{ 1 } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ 4 } \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ 3 } \right )$
$1 - 3 x \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ 4 } \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ 3 } \right )$
$ $ Change the symbol of each term in parentheses when there is a (-) symbol in front of parentheses $ $
$1 - 3 x + \color{#FF6800}{ 4 } \color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ 3 }$
$\color{#FF6800}{ 1 } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ 4 } \color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ 3 }$
$ $ Organize the similar terms $ $
$\left ( \color{#FF6800}{ 1 } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \right ) \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ + } \color{#FF6800}{ 4 } \right ) \color{#FF6800}{ x }$
$\left ( \color{#FF6800}{ 1 } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \right ) + \left ( - 3 + 4 \right ) x$
$ $ Arrange the constant term $ $
$\color{#FF6800}{ - } \color{#FF6800}{ 2 } + \left ( - 3 + 4 \right ) x$
$- 2 + \left ( \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ + } \color{#FF6800}{ 4 } \right ) \color{#FF6800}{ x }$
$ $ Organize the mononomial expression $ $
$- 2 + \color{#FF6800}{ x }$
$\color{#FF6800}{ - } \color{#FF6800}{ 2 } \color{#FF6800}{ + } \color{#FF6800}{ x }$
$ $ Sort the polynomial expressions in descending order $ $
$\color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ 2 }$