You can't go through algebra without seeing quadratic functions. The graphs of quadratic functions are parabolas; they tend to look like a smile or a frown. In this tutorial, get introduced to quadratic functions, look at their graphs, and see some examples of quadratic functions!
When you're trying to graph a quadratic equation, making a table of values can be really helpful. Before you make a table, first find the vertex of the quadratic equation. That way, you can pick values on either side to see what the graph does on either side of the vertex. Watch this tutorial to see how you can graph a quadratic equation!