What Are Intercepts in Math?


What are intercepts in math? I'm Bon Crowder and we're talking about intercepts. The intercepts in math first of all refer to graphs and they mean two things, both Y intercept and X intercept. So an X intercept is where a graph goes through the X axis and a Y intercept is where it goes through the Y axis. Now we've got kind of a crazy graph up here on the top, this is not a function at all, but it is a graph and it does have intercepts. And each of these intercepts have a point associated with them and the X intercepts have some X value, say -85 and the Y value is always 0. So here we might have -72, 0, this might be -3, 0. Obviously not drawn to scale. The Y intercepts, however, have just the opposite. They have 0 as the first coordinate and then a number that's not 0 that's the second, well, it could be 0 actually, that's not fair to say, 0, some other number, some number, say 5. This one could be 0, -1 and maybe -, -27 and notice we have this as an intercept and this as an intercept X intercepts and this one as well. In a function which we have down here, notice we have all these X intercepts but how many Y intercepts do we have? Only 1, so a function has only 1 Y intercept. Y intercepts are like "The Highlander," there can be only 1 for a function. And all these other X intercepts are totally possible. So that is what intercepts mean in math. I'm Bon Crowder, go find you some crazy graphs.

Bon Crowder has taught math to over 15,000 adults in living rooms, classrooms and conferences.