Page 66 - Math 9-10 (2009)

GLOSSARY 65
variable. A symbol used to represent an unspecified number. For example, x and y are variables in the expression x + 2y.
vertex. The point at which two sides of a polygon meet.
x-intercept. The x-coordinate of a point at which a line or curve intersects the x-axis.
xy-plane. A coordinate system based on the intersection of two straight lines called axes, which are usually perpendicular. The horizon- tal axis is the x-axis, and the vertical axis is the y-axis. The point of intersection of the axes is called the origin.
y-intercept. The y-coordinate of a point at which a line or curve intersects the y-axis.
zeros of a relation. The values of x for which a relation has a value of zero. The zeros of a relation correspond to the x-intercepts of its graph. See also x-intercept.