25 terms

4.1 Coordinates and Scatter Plots, p. 203
4.2 Graphing Linear Equations, p. 210
4.3 Quick Graphs Using Intercepts, p. 218
4.4 The Slope of a Line, p. 226
4.5 Direct Variation, p. 234
4.6 Quick Graphs Using Slope-Intercept Form, p. 241
4.7 Solving Linear Equations Using Graphs, p. 250
4.8 Functions and Relations, p. 256

variable expression

a collection of numbers, variables, and operations, p3

solution of an equation

when the variable in a single-variable equation is replaced by a number and the resulting statement is true, p24; in two variables x and y is an ordered pair (x,y) that makes the equation true, p210

function

a rule that establishes a relationship between two quantities, p46

linear equation

the variable is raised to the first power and does not occur in a denominator, inside a square root symbol, or inside absolute value symbols, p133

coordinate plane

formed by two real number lines that intersect at a right angle, p203

ordered pair

each point in the plane corresponds to an _____ _____ of real numbers, p203

x-coordinate

the first number in an ordered pair, p203

y-coordinate

the second number in an ordered pair, p.203

graph

the point in the plane that corresponds to an ordered pair (x,y), p203

scatter plot

one way to analyze the relationships between two quantities is to graph the pairs of data on a coordinate axis, p204

graph of a linear equation

in x and y is the set of all points (x,y) that are solutions of the equation, p210

line

graph of a linear equation, p210

x-intercept

x-coordinate of a point where a graph crosses the x-axis, 218

y-intercept

y-coordinate of a point where a graph crosses the y-axis, 218

slope

m of a nonvertical line is the number of units the line rises or falls for each unit of horizontal change from left to right, 226

rate of change

compares two different quantities that are changing, p229

velocity

the rate at which distance is changing with time, p229

constant of variation

two variables x and y vary directly if there is a nonzero number k such is true that the number k is the _______ _______, p234

direct variation

two quantities that vary directly are said to have ______ _______, p234

slope of the intercept form

the linear equation y=mx+b is written in _____ _____, p241

m

the slope of the line, p241

b

the y-intercept, p241

parallel

two different lines in the same plane that do no intersect, p242

function notation

in general, the symbol f(x) replaces y and is read as "the value of f at x" or simply as "f of x" which does not mean f times x where f is called _______ ________, p257

graph of a function

since function notation allows you to write f(x) in place of y, the ______ ___ __ _______ f is the set of all points (x, f(x)), where x is in the domain of the function, p257