Chapter 1 Vocabulary - Ratios and Proportional Reasoning

constant of proportionality

A constant ratio or unit rate of two variable quantities. It is also called "constant of variation."

complex fraction

A fraction A/B where A and/or B are fractions, and B does not equal zero.

ordered pair

A pair of numbers that can be used to locate a point on a coordinate plane. An ___________ is writing in the form (x, y)

rate of change

A rate that describes how one quantity changes in relation to another. A rate of change is usually expressed as a unit rate.

rate

A ratio that compare two quantities measured in different kinds of units. Example: mph (miles per hour)

proportion

An equation stating that two ratios or rates are equal/equivalent. Example: 1/4 = 3/12

origin

The point (0,0) where the x-axis and the y-axis intersect in a coordinate plane.

y-coordinate

The second number of an ordered pair. It corresponds to a number on the y-axis

proportional

Two quantities that have a constant rate or ratio.

equivalent ratios

Two ratios that have the same value. Example: 2/4 = 1/2

coordinate plane

A plane in which a horizontal number line and a vertical number line intersect at their zero points. Also called a "coordinate grid."

quadrants

One of the four regions into which the two perpendicular number lines of the coordinate plane separate the plane.

constant of variation

The constant ratio in a direct variation. It is also called "constant of proportionality."

x-coordinate

The first number of an ordered pair. It corresponds to a number on the x-axis.

x-axis

The horizontal number line in a coordinate plane

dimensional analysis

The process of including units of measurement when you compute.

cross products

The product of the numerator of one ratio and the denominator of the other ratio. The cross products of any proportion are equal.

slope

The rate of change between any 2 points on a line. It is the ratio of vertical change to horizontal change. The ________tells how steep the line is (rise over run).

constant rate of change

The rate of change in a linear relationship.

nonproportional

The relationship between two ratios with a rate or ratio that is not constant.

y-axis

The vertical number line in a coordinate plane.