Abscissa - The horizontal line, or x-axis, of a graph.
Arc - A portion of the circumference of a circle.
Axis - One of the lines that is used to form a graph. There is the horizontal x-axis and the vertical y-axis in a two dimensional graph.
Example of x-axis, y-axis, and coordinates on a graph
Bisect - To bisect an object is to divide it into two equal halves.
Collinear - A set of three or more points that are lying on the same straight line are collinear.
Coordinates - A set of two numbers that indicate where a point is on a graph. The first number indicates the x-axis and the second number the y-axis. Other names include ordered pair and numbered pair.
Coplanar lines - Two or more lines that are on the same plane or flat surface.
Diameter - A line segment that passes through the center of a circle with each end point being on the circumference.
Endpoint - The point at the end of a line segment or ray.
Horizontal - A flat or level line or plane that is perpendicular to the vertical.
Intersecting lines - Two or more lines that meet at a point are intersecting.
Line - A straight object that is infinitely long and thin. It is only in one dimension.
Line segment - A portion of a line with two endpoints.
Midpoint - The point of a line segment that is the same distance from both endpoints.
Noncollinear points - A set of three points that are not located on the same line.
Number pair - Two numbers that represent a point on a graph, also called the coordinates.
Ordinate - The vertical line, or y-axis, of a graph.
Origin - The origin is the point where the X and Y axis intersect on a graph. This is the point (0,0) in a two-dimensional graph.
Parallel lines - Lines that never intersect or cross are parallel lines.
Parallel lines
Perpendicular lines - Two lines that form a right angle (90 degrees) are perpendicular lines.
Perpendicular lines
Ray - A line that has one endpoint, but extends forever in one direction.
Slope - A number that indicates the incline or steepness of a line on a graph. Slope equals the "rise" over the "run" of a line on a graph. This can also be written as the change in y over the change in x.
Example: If two points on a line are (x1, y1) and (x2, y2), then the slope = (y2 - y1) ÷ (x2-x1).
Tangent - A line that touches an object such as an arc or circle at a single point.
The green line is tangent to the circle
Transversal - A transversal is a line that crosses two or more other lines.
Vertical - A line or plane that is upright and perpendicular to the horizontal.