The graph provided shows a quadratic function in the form of a parabola, and the vertex of the parabola is at the point (0, 4). The parabola opens downwards, indicating a maximum value at the vertex.

To find the range:

• The maximum value of the quadratic function is $y = 4$ (from the vertex).
• Since the parabola opens downward, the values of $y$ decrease without bound.

Thus, the range of the quadratic function is: $(-\infty, 4]$

Would you like more details or have any questions?

Here are 5 related questions to deepen understanding:

1. How do you find the vertex of a quadratic function given its equation?
2. What is the significance of the direction in which the parabola opens?
3. How can you determine the domain of a quadratic function?
4. What does it mean for a quadratic function to have a maximum or minimum value?
5. How do transformations affect the range of a quadratic function?

Tip: In any quadratic function $f(x) = ax^2 + bx + c$, if $a > 0$, the parabola opens upwards (minimum value); if $a < 0$, it opens downwards (maximum value).