proportional relationships

proportional relationships

A proportional relationship is one in which the ratio of the inputs to the outputs is constant. For a relationship to illustrate a proportional relationship, all the ratios y _ x or _x y, must represent the same constant.

constant of proportionally

In a proportional relationship, the ratio of all y-values to their corresponding x-values is constant. This specific ratio, y _ x, is called the constant of proportionality. Generally, the variable k is used to represent the constant of proportionality.

slope

In any linear relationship, slope describes the direction and steepness of a line and is usually represented by the variable m. Slope is another name for rate of change. (See rate of change.)

point slope form

The point-slope form of a linear equation is y 2 y1 5 m(x 2 x1), where m is the slope of the line and (x1, y1) is any point on the line.

rate of change

The rate of change for a situation describes the amount that the dependent variable changes compared with the amount that the independent variable changes.

slope intercept form

The slope-intercept form of a linear equation is y 5 mx 1 b, where m is the slope of the line and (0, b) is the y-intercept.

slandard form

The standard form of a linear equation is Ax 1 By 5 C, where A, B, and C are constants and A and B are not both 0.

y- intercept

The y-intercept is the y-coordinate of the point where a graph crosses the y-axis. The