Final answer:
The set builder notation for 'The set of all x such that x is a number greater than or equal to 5' is written as x ≥ 5, where the vertical bar means 'such that' and the condition is that x must be greater than or equal to 5.
Step-by-step explanation:
To express the phrase 'The set of all x such that x is a number greater than or equal to 5' in set builder notation, you would write it as follows:
x ≥ 5
This notation includes curly braces that denote a set, a variable (in this case, x), a vertical bar that can be read as 'such that', and a condition that the elements of the set must satisfy (x is greater than or equal to 5).