Lots of points.
1 function or not

explain when you get the answer

2
function or not

explain when you have the answer

3
function or not

explain when you have the answer

Problem 1

The set below

{(-3,0), (13,4), (6, 3), (13, -4), (22, 5)}

is not a function. Focus on these two points (13,4) and (13,-4)

The input x = 13 leads to two different outputs y=4 and y = -4 at the same time. This is why we dont have a function. Any given input must point to exactly one output (assuming this input is in the domain of course)

Problem 2

This is a function. It is impossible to draw a single vertical line through more than one point on the curve shown. This means the graph passes the vertical line test.

Problem 3

y = -3x^2 + 10 is a function. Any input x leads to exactly one y output. The graph passes the vertical line test.

a² + b²= c²

24² + 7² = c²

c= 25