Year 9 Linear Relationships
Linear relationship
A set of ordered pairs that give a straight line
Horizontal line: y = b
Parallel to the x-axis, the y-coordinate is the same for every point on the line.
Vertical line: x = a
Parallel to the y-axis, the x-coordinate is the same for every point on the line.
The origin.
The point (0, 0) where the x-axis and y-axis intersect at right angles.
The Cartesian plane (or number plane)
consists of two axes that divide the number plane into four quadrants.
The gradient
is a measure of its steepness or slope.
y = mx + b
is the gradient-intercept form of a straight line equation. m is the gradient b is the y intercept
The x-axis
is the horizontal axis.
The y-axis
is the vertical axis.
The midpoint (M) of a line segment
the halfway point between the two endpoints.
The x-intercept
the x-value of the point where the line cuts (intersects) the x-axis.
The y-intercept
the y-value of the point where the line cuts (intersects) the y-axis.