Proportional Relationships

Vocabulary flashcards covering key terms about proportional relationships from the lecture notes.

Proportional relationship

A relationship between two quantities where the ratio is constant; the graph is a straight line through the origin and y = kx for some constant k.

Constant ratio

A fixed value for the ratio of two proportional quantities; the ratio remains the same across all pairs.

Origin

The point (0, 0) on a Cartesian plane; the starting point for graphs of proportional relationships.

Straight line through the origin

A line that passes through (0,0), indicating y is directly proportional to x (y = kx).

Proportion

An equation stating that two ratios are equal (for example, a/b = c/d).

Write and solve proportions

The process of setting up a proportion and solving for an unknown quantity.

Ratio

A comparison of two quantities expressed as a fraction, a/b, or as a:b.

Identify proportional relationships

Determining whether two quantities are proportional by checking for a constant ratio or for a graph that passes through the origin.

Graph of two quantities

A plot with the two quantities on the axes to visualize how one changes with the other.