Answers:
- A) No, it is not a function
- B) Yes it's a function
- C) Not a function
- D) Yes it's a function
- E) Yes it's a function
================================================
Explanation:
If y has an exponent of 2, 4, 6, etc (basically any even number) then it leads to having inputs with multiple outputs.
Consider something like y^2 = x. If x = 100, then y = 10 or y = -10 are possible. A function can only have exactly one y output for any valid x input. Similar issues happen for things like y^4 = x and so on. So this is why A and C are not functions.
The other equations do not have y values with such exponents, so we can solve for y and have each x input lead to exactly one y output. Therefore, they are functions.
