Y-intercept

In analytic geometry, using the common convention that the horizontal axis represents a variable

and the vertical axis represents a variable

-intercept or vertical intercept is a point where the graph of a function or relation intersects the

-axis of the coordinate system.

[1] As such, these points satisfy

If the curve in question is given as

-intercept is found by calculating

Functions which are undefined at

If the function is linear and is expressed in slope-intercept form as

, the constant term

[2] Some 2-dimensional mathematical relationships such as circles, ellipses, and hyperbolas can have more than one

Because functions associate

-value as part of their definition, they can have at most one

-intercept is a point where the graph of a function or relation intersects with the

As such, these points satisfy

The zeros, or roots, of such a function or relation are the

-intercepts of functions, if any exist, are often more difficult to locate than the

-intercept involves simply evaluating the function at

The notion may be extended for 3-dimensional space and higher dimensions, as well as for other coordinate axes, possibly with other names.

-intercept of the current–voltage characteristic of, say, a diode.

(In electrical engineering,

is the symbol used for electric current.)