Short Answer 
The vertical line test is used to determine if a graph represents a valid function by checking if a vertical line intersects the graph at more than one point. If it intersects at one point, it’s a valid function; if at multiple points, it’s not. Additionally, you should evaluate the inverses of the functions to see if they also pass the vertical line test.
Step 1: Understand the Vertical Line Test
The vertical line test is a method used to determine if a graph represents a valid function. To conduct this test, you imagine a vertical line moving across your graph from left to right. If the vertical line intersects the graph at more than one point simultaneously, then the graph does not represent a function.
Step 2: Apply the Test to Different Lines
When applying the vertical line test, analyze each line on your graph. Check whether the vertical line touches it at:
- One point ‚ÄöAi Indicates a valid function.
- Multiple points ‚ÄöAi Indicates that it is not a valid function.
The first line and its inverse demonstrate a valid function, while others may vary based on their inverses.
Step 3: Evaluate Inverses of the Lines
After determining that a line is a valid function, assess its inverse. This means checking if the inverse function also passes the vertical line test. The first line and its inverse pass, but for subsequent lines, their inverses might fail the test, indicating they are not valid functions.