One type of problem that involves quadratic functions presents you with a set of points that lie on a parabola and asks you to select the quadratic function that matches:

One direct way to solve this problem in Desmos is to use the powerful regression feature. To find the coefficients and constants needed for a quadratic, you can enter into a table three points that lie on the parabola (you need at least three points, and there's no reason to enter more), then set up a regression statement in the format of the provided answer choices (remember, you'll use the regression operator ~ where you'd use = in an equation); here, they're all in vertex form. Then, all you have to do is to match the coefficient and constant values a, h, and k to those of one of the answer choices. Pretty slick.

Answer: D