By definition, when you graph a Quadratic function you get a parabola.
The Parent function of the Quadratic functions is:

The parabola of the Parent function is:
You can notice that its vertex is at the Origin and it opens upward.
In this case you have this Quadratic function:

You can identify that it's like the form of the Parent function, but it has a negative coefficient that is multiplying the variable. Then:
- Since the coefficient is negative, the parabola opens downwards.
- The vertex of the parabola is at the Origin.
Now you can give values to "x" in order to make a table and find points on the parabola:
1. When

You get:

2. When

You get:

3. When

You get:

4. When

You get that:

5. When

You get:

Now you can make the table. This is:
Finally, you have to plot the points on the Coordinate plane in order to graph the function.
The answer is: