I need help determining the function that is shown in the graph.

This is a piecewise function, where the two equations are different. They are:
[tex]\begin{gathered} y=x^2+4 \\ y=-x+4 \end{gathered}[/tex]The function x² + 4 is graphed where x < 2. (< is used because the circle is open)
The function -x + 4 is graphed where x ≥ 2. (≥ is used since the endpoint is closed)
Therefore, the answer is:
[tex]\begin{gathered} x^2+4,x<2 \\ -x+4,x\ge2 \end{gathered}[/tex]