One of the main reasons we study quadratics is to use a quadratic function to model anything that is flying through the air. You'll see this a lot in physics. The independent variable, usually called x, will now be called t for time, and the dependent variable, y, is now called h for height. To find the maximum height, we'll need to find the vertex by either completing the square or using t = -b/2a and plugging that in to find the corresponding height. To find the initial launch height, we let time be zero. To find total time in the air, we let height be zero and solve for x by either factoring or using the quadratic formula. These problems take practice, but don't skip them- they finally put together all of the quadratic skills that you have developed.