Answer:
x=4
Step-by-step explanation:
Realize that a function can only have one output, y, for each unique input, x.
<u>2 Methods on finding if something is a function or not.</u>
Do the vertical function test
To use the vertical line test, take a ruler or other straight edge and draw a line parallel to the y-axis for any chosen value of x. If the vertical line you drew intersects the graph more than once for any value of x then the graph is not the graph of a function.
Plug in points! See if there are more than one outputs for y
