An experiment by Galileo in 1609 shown a parabola for an object falling with horizontal motion. In TI Nspire, graphing the scatter plot is done by using the “Data and Statistics” page, and then clicking on the X and Y caption for respective data dimension.
Adding regression line is also easy by selecting the Analyze > Regression menu and then apply the regression model.
The regression line will then be plotted against the scatter plot.
To decide which one fits better, the R2 can be deduced by running the Quadratic Regression and Cubic Regression in the List and Spreadsheet page.