Answer:
Both figures on the right are functions (the one that is already marked and the one below it ).
Step-by-step explanation:
A relationship between two variables is a function when it fulfill two requirements: <u>existence</u> and <u>uniqueness</u>.
The first one (existence) imply that every possible value of the independent variable (x) must be linked with a value of the independent variable (y). This means that for every value of x it must be a correspondent value of y.
The second requirement (uniqueness) means that every value of the independent variable (x) is linked with <u>a single</u> value of the the dependent variable (y)
A relationship between two variables x and y is not a function if it doesn’t meet these requirements.
In the pictures you have attached, the images in the left side of the page, are not functions because they don’t meet the requirement of uniqueness. The upper picture on the left for example, assigns two different values of y to x=0 (when x=0, y can take the value of -2 or 2), while the lower picture on the left does exactly the same with every value of x different from zero (when x=3 for example, y takes two values: -3 and 3). This means that these arerelationships but not functions.
