The "Vertical Line Test"

The "Vertical Line Test"

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Vertical line test is relation between two terms of X and Y. And this test used to determine If a relation is a function. If that shows no vertical lines and that intersect the graph at more than one point, the relation for each element of the domain are corresponding to exactly one element of the range.

Types of lines
Line:
The infinitely long and thin of the straight geometrical object is called line. Types of lines can be classified into following types:

• Straight Line
• Vertical line
• Horizontal line

Looking at this function stuff graphically, what if we had the relation that consists of a set containing just two points: {(2, 3), (2, –2)}? We already know that this is not a function, since x = 2 goes to each of y = 3 and y = –2.This characteristic of non-functions was noticed by I-don't-know-who, and was codified in "The Vertical Line Test": Given the graph of a relation, if you can draw a vertical line that crosses the graph in more than one place, then the relation is not a function. Here are a couple examples: