Q:

2|x-2|+|x+2|<=10

Accepted Solution

A:
Separate the inequality into $4$ possible cases
$\begin{array} { l }\begin{array} { l }2\left( x-2 \right)+x+2 \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)+x+2 \leq 10,& \begin{array} { l }x-2 < 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x-2 \geq 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)+x+2 \leq 10,& \begin{array} { l }x-2 < 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)+x+2 \leq 10,& \begin{array} { l }x-2 < 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)+x+2 \leq 10,& \begin{array} { l }x-2 < 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x-2 < 0,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x+2 \geq 0\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }2\left( x-2 \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x-2 \geq 0,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x+2 < 0\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }2 \times \left( -\left( x-2 \right) \right)-\left( x+2 \right) \leq 10,& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x-2 < 0,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x < 2,& x+2 < 0\end{array}\end{array}\end{array}$
Solve the inequality for $x$
$\begin{array} { l }\begin{array} { l }x \leq 4,& \begin{array} { l }x \geq 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x < 2,& x < -2\end{array}\end{array}\end{array}$
Find the intersection
$\begin{array} { l }\begin{array} { l }x \leq 4,& x \in \left[ 2, +\infty\right\rangle\end{array},\\\begin{array} { l }x \geq -4,& \begin{array} { l }x < 2,& x \geq -2\end{array}\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x < 2,& x < -2\end{array}\end{array}\end{array}$
Find the intersection
$\begin{array} { l }\begin{array} { l }x \leq 4,& x \in \left[ 2, +\infty\right\rangle\end{array},\\\begin{array} { l }x \geq -4,& x \in \left[ -2, 2\right\rangle\end{array},\\\begin{array} { l }x \leq 16,& \begin{array} { l }x \geq 2,& x < -2\end{array}\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x < 2,& x < -2\end{array}\end{array}\end{array}$
Find the intersection
$\begin{array} { l }\begin{array} { l }x \leq 4,& x \in \left[ 2, +\infty\right\rangle\end{array},\\\begin{array} { l }x \geq -4,& x \in \left[ -2, 2\right\rangle\end{array},\\\begin{array} { l }x \leq 16,& ∅\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& \begin{array} { l }x < 2,& x < -2\end{array}\end{array}\end{array}$
Find the intersection
$\begin{array} { l }\begin{array} { l }x \leq 4,& x \in \left[ 2, +\infty\right\rangle\end{array},\\\begin{array} { l }x \geq -4,& x \in \left[ -2, 2\right\rangle\end{array},\\\begin{array} { l }x \leq 16,& ∅\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& x \in \langle-\infty, -2\rangle\end{array}\end{array}$
Find the intersection
$\begin{array} { l }x \in \left[ 2, 4\right],\\\begin{array} { l }x \geq -4,& x \in \left[ -2, 2\right\rangle\end{array},\\\begin{array} { l }x \leq 16,& ∅\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& x \in \langle-\infty, -2\rangle\end{array}\end{array}$
Find the intersection
$\begin{array} { l }x \in \left[ 2, 4\right],\\x \in \left[ -2, 2\right\rangle,\\\begin{array} { l }x \leq 16,& ∅\end{array},\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& x \in \langle-\infty, -2\rangle\end{array}\end{array}$
Find the intersection
$\begin{array} { l }x \in \left[ 2, 4\right],\\x \in \left[ -2, 2\right\rangle,\\∅,\\\begin{array} { l }x \geq -\frac{ 8 }{ 3 },& x \in \langle-\infty, -2\rangle\end{array}\end{array}$
Find the intersection
$\begin{array} { l }x \in \left[ 2, 4\right],\\x \in \left[ -2, 2\right\rangle,\\∅,\\x \in \left[ -\frac{ 8 }{ 3 }, -2\right\rangle\end{array}$
Find the union
$\begin{align*}&x \in \left[ -\frac{ 8 }{ 3 }, 4\right] \\&\left\{ \right\}\end{align*}$