HELP ! I have no access to a math book over the Holidays and am trying to help my son before his math test Tuesday. I am an ex-electrical engineer and have the math background but its rusty. What are the vertices of a hyperbola ? Are they the points on each hyperbola closest to each other, e.g. at the 'peaks' of the hyperbolas ? And is there a formula for determining them ? When the two closest points are on the x axis or y axis I remember how to find them by setting y or x equal to zero and solving for the intercepts. But what if the hyperbolas are not vertically or horizontally aligned along the axis but rather offset ? Thanks and happy Holidays ! BTW is there a website that has a tutorial on parabolas ?