Answer:
No.
Step-by-step explanation:
A function must past the Vertical Line Test. We know that our equation x² + y² = 5 is a circle, and so some x-values have the same y-values, etc. Since not every x-value has its own y-value, our equation is not a function.
We can see this using a graph:
Since the vertical line test passes 2 points with the same x-value, it is not a function.
