Question

Determine whether the following equation defines y as a function of x. x^2 + y^2 =169

Answer 1

The graph of this is a circle of radius 13 centered at the origin. Does it pass the vertical line test?

Answer 2

no

Answer 3

So, is it a function?

Answer 4

no?

Answer 5

Be more confident! You are correct.

Answer 6

Remember, the vertical line test is a graphic test for functions. If any vertical line hits the graph more than once, the relation is not a function. That is exactly what happens in this case.