Question

Find the domain of the relation.

Answer 1

• Domain: List of x-values that apply to the line.
• Range: List of y-values that apply to the line.
• Function: A relation that has every input (x) only have 1 output (y).
• Interval Notation: Lists the endpoint(s) of a line, and whether it's a bracket or a parenthesis on the end determines whether the endpoint is included on the line. (e.g: [17,20). 17 is included in the line, 20 is not.)

Looking at the domain, the lines will continue to stretch infinitely. Therefore, the domain is $[-\infty,\infty]$

Now looking at the range, the line stops at y = 1 and goes infinitely beyond it. Therefore, the range is $[1,\infty]$

Now lastly, to figure out if the relation is a function, conduct the vertical test. Since a definition of a function is that every input (x) has only 1 output (y), taking something vertical and sliding it across the graph should show only one point vertically. Since every x-value only has one y-value in this case, this relation is a function.