The points where a graph crosses the x- and y-axes are called the x-intercept and y-intercept, respectively.
Sometimes, only one coordinate of these points is referenced. For example, since the x-intercept lies at (a,0), it can be said that x=a. The same is true for the y-intercept (0,b), y=b. A relation can have several intercepts; a function can have multiple x-intercepts, but it can only have one y-intercept.