Glossary Term voluntary response sample weighted average Definition A sample that involves only those who want to participate. whole numbers x-axis The sum of the product of the number of units and the value per unit divided by the sum of the number of units. The segments extending from the ends of the box in a box-andwhisker plot. The set {0, 1, 2, 3, …}. The horizontal number line on a coordinate plane. x-coordinate x-intercept yard y-axis The first number in an ordered pair. The x-coordinate at which a graph intersects the x-axis. A customary unit of length. 1 yard = 3 feet = 36 inches The vertical number line on a coordinate plane. y-coordinate y-intercept zero exponent zero matrix zero pair Zero Product Property The second number in an ordered pair. The y-coordinate at which a graph intersects the y-axis. For any nonzero number a, a0 = 1. A matrix in which every element is zero. The result of a positive counter paired with a negative counter. For all numbers a and b, if ab = 0, then a = 0, b = 0, or both a and b equal zero. zero vector zeros A vector with initial and terminal points at the origin. The roots, or x-intercepts, of a function. whisker