Answer
\[\left| x \right| = \left\{ {\begin{array}{*{20}{c}}
{x\,\,\,\,\,\,\,\,\,\,{\text{if }}x \geqslant 0} \\
{ - x\,\,\,\,\,\,\,{\text{if }}x < 0}
\end{array}} \right.\]
Work Step by Step
\[\begin{gathered}
{\text{The absolute value of a real number is defined as:}} \hfill \\
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left| x \right| = \left\{ {\begin{array}{*{20}{c}}
{x\,\,\,\,\,\,\,\,\,\,{\text{if }}x \geqslant 0} \\
{ - x\,\,\,\,\,\,\,{\text{if }}x < 0}
\end{array}} \right. \hfill \\
\end{gathered} \]
