02A-W3209 2/11/05 4:12 PM Page 98
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Chapter 2 Graphs, Equations of Lines, and Functions
Check Your Knowledge
1. In the ordered pair (5, 13), the number 5 is called the
13 is called the
coordinate and
coordinate.
2. The graph of an equation is the graph of all points (x, y) on the rectangular
coordinate system whose coordinates
the equation.
3. Any equation whose graph is a straight line is called a
equation.
4. Two lines are
when their slopes are negative reciprocals. Two
lines are
when they have the same slope.
5. The set of all output values of a function is called the
inputs is called the
and the set of all
of the function.
6. Use the graph in the illustration to answer the
y
following questions.
x
a. What are the values of x when y 0?
b. What is the y-intercept of the graph?
c. What is the minimum y value?
y
7. Find the midpoint of the line segment joining
y = x2 + 2x – 8
(2, 7) and (5, 2).
x
8. Find the x- and y-intercepts of the graph of
PROBLEM 6
2x 3y 6. Then graph the equation.
Fnd the slope of each line, if possible.
PROBLEM 8
9.
10.
11.
12.
y
The graph of x 3
The line through (2, 3) and (3, 2)
The graph of 4x 2y 7
Find the slope of the line shown in the illustration.
13. Write an equation of the line with slope 2 that passes through (2, 7). Give the
answer in slope–intercept form.
x
14. Write an equation of the line that passes through the points (2, 1) and (1, 4).
Give the answer in general form.
15. Write an equation of the line that passes through the origin and is perpendicular
to the graph of y x 2. Give the answer in slope–intercept form.
PROBLEM 12
16. Does y2 x define y to be a function of x?
1
x
17. Find the domain and range of the function f(x) .
18. Consider f(x) 2x2 3x 2.
a. Find f(1).
b. Find f(0).
19. Which of the following are graphs of functions?
y
y
a.
b.
y
x
PROBLEM 20
x
20. Graph: f(x) x2 2.
c.
x
y
x