The equation for the given relation is a quadratic equation:
[tex]y = x^2[/tex]
Here we have the relation:
D = {(x, y); (3, 9), (5, 25), (-2, 4), ...}
Notice that for each coordinate point, we can see that the output is equal to the square of the input:
[tex]3^2 = 9\\5^2 = 25\\(-2)^2 = 4[/tex]
Then the equation is just:
[tex]y = x^2[/tex]
If you want to learn more about quadratic equations:
https://brainly.com/question/1214333
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