## Thinking Mathematically (6th Edition)

The set- builder notation for all real numbers that satisfy the given condition is $\left\{ x|x\le 5 \right\}$
Let us suppose the number is$x$. Then, the algebraic form of the inequality is: $x+5\ge 2x$ And now to find out possible values of $x$ satisfying the inequality the inequality is solved as follows: \begin{align} & x+5\ge 2x \\ & 5\ge 2x-x \\ & 5\ge x \\ & x\le 5 \end{align} Hence all the real numbers less than or equal to 5 will satisfy the condition. The set-builder form of the inequality obtained is: $\left\{ x|x\le 5 \right\}$ The set- builder notation for all real numbers that satisfy the given condition is $\left\{ x|x\le 5 \right\}$