Question

Is y = 2x a function? yes or no

Answer 1

Yes, using the vertical line test can show you so

Answer 2

Yes.

Explanation:

A good test to do is the vertical line test. You draw the equation you're trying to determine is or isn't a function, and then draw a vertical line through it, if it goes through once it is a function. If twice then it is not a function. Hope this helps. :)