coordinate

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In geometry, a number that defines the position of a point relative to a point or axis (reference line). Cartesian coordinates define a point by its perpendicular distances from two or more axes drawn through a fixed point mutually at right angles to each other. Polar coordinates define a point in a plane by its distance from a fixed point and direction from a fixed line.

When working on the two-dimensional plane the coordinates can be plotted on a graph.

The coordinates of the points A, B, C, and D are: A (3, 1), B (-3, 2), C (-1, -4), D (3, -2). Coordinates can, therefore, be both positive numbers, both negative numbers, or a positive and a negative number. The x- and y-axes intersect to create four quadrants.

Once plotted, coordinates can be joined up to obtain straight-line graphs from linear equations or curves from quadratic equations and cubic equations. The intercept and gradient can be calculated.

Distance–time graphs and conversion graphs are both obtained by plotting coordinates.

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