Document 6608595

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Document 6608595
function.
Study Guide and Review - Chapter 4
State whether each sentence is true or false . If
false , replace the underlined term to make a
true sentence.
2. The process of using a linear equation to make
predictions about values that are beyond the range of
the data is called linear regression.
SOLUTION: The statement is false. The process of using a linear
equation to make predictions about values that are
beyond the range of the data is called linear
extrapolation. Linear regression is an algorithm to
find a precise line of fit for a set of data. 4. The correlation coefficient describes whether the
correlation between the variables is positive or
negative and how closely the regression equation is
modeling the data.
SOLUTION: The range of a relation is the domain of the inverse
of the relation. The statement is false. Write an equation of a line in slope-intercept
form with the given slope and y-intercept. Then
graph the equation.
10. slope: 3, y-intercept: 5
SOLUTION: The slope-intercept form of a line is y = mx + b,
where m is the slope, and b is the y-intercept.
To graph the equation, plot the y-intercept (0, 5).
Then move down 3 units and left 1 unit. Plot the
point. Draw a line through the two points.
SOLUTION: The correlation coefficient describes whether the
correlation between the variables is positive or
negative and how closely the equation is modeling the
data. So, the statement is true.
6. Lines that intersect at acute angles are called
perpendicular lines.
SOLUTION: The statement is false. Lines that intersect at right
angles are called perpendicular lines. Acute angles
have measures less than 90. 8. The range of a relation is the range of its inverse
function.
SOLUTION: The range of a relation is the domain of the inverse
of the relation. The statement is false. 12. slope:
, y-intercept: 3
SOLUTION: The slope-intercept form of a line is y = mx + b,
where m is the slope, and b is the y -intercept.
Write an equation of a line in slope-intercept
form with the given slope and y-intercept. Then
graph the equation.
10. slope: 3, y-intercept: 5
SOLUTION: The slope-intercept form of a line is y = mx + b,
where m is the slope, and b is the y-intercept.
To graph the equation, plot the y-intercept (0, 3).
Then move up 2 units and right 3 units. Plot the point.
Draw a line through the two points.
To graph the equation, plot the y-intercept (0, 5).
left 1 unit. Plot the
point. Draw a line through the two points.
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Study Guide and Review - Chapter 4
12. slope:
, y-intercept: 3
SOLUTION: The slope-intercept form of a line is y = mx + b,
where m is the slope, and b is the y -intercept.
16. SOLUTION: To graph the equation, plot the y-intercept (0, 1).
Then move up 1 unit and right 2 units. Plot the point.
Draw a line through the two points.
To graph the equation, plot the y-intercept (0, 3).
Then move up 2 units and right 3 units. Plot the point.
Draw a line through the two points.
18. SKI RENTAL Write an equation in slope-intercept
form for the total cost of skiing for h hours with one
lift ticket.
Graph each equation.
14. y = 4x − 2
SOLUTION: To graph the equation, plot the y-intercept (0, −2).
Then move up 4 units and right 1 unit. Plot the point.
Draw a line through the two points.
SOLUTION: The rate of $5 per hour represents the rate or slope.
The cost of the lift ticket is a constant $15, no matter
how many hours you ski. So, the total cost of skiing
for h hours can be written as y = 5h + 15.
Write an equation of the line that passes
through the given point and has the given
slope.
20. (2, −6), slope −4
SOLUTION: Find the y-intercept.
Write the equation in slope-intercept form.
16. SOLUTION: To graph the equation, plot the y-intercept (0, 1).
Then move up 1 unit and right 2 units. Plot the point.
Draw a line through the two points.
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22. (5, −2), slope
SOLUTION: The rate of $5 per hour represents the rate or slope.
The cost of the lift ticket is a constant $15, no matter
how
manyand
hours
you ski.
So, the total
Study
Guide
Review
- Chapter
4 cost of skiing
for h hours can be written as y = 5h + 15.
Write an equation of the line that passes
through the given point and has the given
slope.
20. (2, −6), slope −4
SOLUTION: Find the y-intercept.
Write an equation of the line that passes
through the given points.
24. (−4, 3), (1, 13)
SOLUTION: Find the slope of the line containing the given points.
Write the equation in slope-intercept form.
Use the slope and either of the two points to find the
y-intercept.
22. (5, −2), slope
SOLUTION: Find the y-intercept.
Write the equation in slope-intercept form.
26. (2, 4), (7, 2)
SOLUTION: Find the slope of the line containing the given points.
Write the equation in slope-intercept form.
Write an equation of the line that passes
through the given points.
24. (−4, 3), (1, 13)
SOLUTION: Find the slope of the line containing the given points.
Use the slope and either of the two points to find the
y-intercept.
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Write the equation in slope-intercept form.
SOLUTION: Study Guide and Review - Chapter 4
26. (2, 4), (7, 2)
SOLUTION: Find the slope of the line containing the given points.
Write each equation in standard form.
32. y − 7 = −3(x + 1)
SOLUTION: 34. y − 9 =
(x + 2)
Use the slope and either of the two points to find the
y-intercept.
SOLUTION: Write the equation in slope-intercept form.
Write each equation in slope-intercept form.
36. y − 12 = −2(x − 3)
SOLUTION: Write an equation in point-slope form for the
line that passes through the given point with
the slope provided.
28. (6, 3), slope 5
38. y − 4 =
(x + 2)
SOLUTION: SOLUTION: 30. (−4, 2), slope 0
SOLUTION: Write each equation in standard form.
32. y − 7 = −3(x + 1)
SOLUTION: eSolutions Manual - Powered by Cognero
Write an equation in slope-intercept form for
the line that passes through the given point and
is parallel to the graph of each equation.
40. (0, 3), y = 3x + 5
SOLUTION: The slope of the line with equation y = 3x + 5 is Page
3. 4
The line parallel to y = 3x + 5 has the same slope, 3.
Study Guide and Review - Chapter 4
Write an equation in slope-intercept form for
the line that passes through the given point and
is parallel to the graph of each equation.
40. (0, 3), y = 3x + 5
SOLUTION: The slope of the line with equation y = 3x + 5 is 3.
The line parallel to y = 3x + 5 has the same slope, 3.
Write an equation in slope-intercept form for
the line that passes through the given point and
is perpendicular to the graph of the given
equation.
44. (1, 3), y = −2x − 4
SOLUTION: The slope of the line with equation y = −2x − 4 is −2.
The slope of the perpendicular line is the opposite
reciprocal of −2, or
.
42. (−5, −2), y =
x+4
SOLUTION: The slope of the line with equation y =
x + 4 is
46. (3, 0), y =
. The line parallel to y =
x
x + 4 has the same
SOLUTION: slope,
.
The slope of the line with equation y =
x is
.
The slope of the perpendicular line is the opposite
reciprocal of
, or 2.
Write an equation in slope-intercept form for
the line that passes through the given point and
is perpendicular to the graph of the given
equation.
44. (1, 3), y = −2x − 4
SOLUTION: The slope of the line with equation y = −2x − 4 is −2.
The slope of the perpendicular line is the opposite
reciprocal of −2, or
48. ATTENDANCE A scatter plot of data compares
the number of years since a business has opened and
its annual number of sales. It contains the ordered
pairs (2, 650) and (5, 1280). Write an equation in
slope-intercept form for the line of fit for this
situation.
SOLUTION: Find the slope of the line containing the given points.
.
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of fit.
Study Guide and Review - Chapter 4
48. ATTENDANCE A scatter plot of data compares
the number of years since a business has opened and
its annual number of sales. It contains the ordered
pairs (2, 650) and (5, 1280). Write an equation in
slope-intercept form for the line of fit for this
situation.
SOLUTION: Find the slope of the line containing the given points.
50. MOVIES The table shows ticket sales at a certain
theater during the first week after a movie opened.
Write an equation of the regression line. Then
estimate the daily ticket sales on the 15th day.
SOLUTION: Use a calculator to find the equation of the
regression line.
Use the slope and either of the two points to find the
y-intercept.
y = −5.79x + 99.14
To estimate the daily ticket sales on the 15th day,
evaluate the regression equation for x = 15.
Write the equation in slope-intercept form for the line
of fit.
50. MOVIES The table shows ticket sales at a certain
theater during the first week after a movie opened.
Write an equation of the regression line. Then
estimate the daily ticket sales on the 15th day.
SOLUTION: Use a calculator to find the equation of the
regression line.
The daily ticket sales on the 15th day after a movie
opens is $12.29.
Find the inverse of each relation.
52. {(1, 9), (13, 26), (–3, 4), (–11, –2)}
SOLUTION: To find the inverse, exchange the coordinates of the
ordered pairs.
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(1, 9) → (9, 1)
(13, 26) → (26, 13)
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(–4, –4) → (–4, –4)
(0, –8) → (–8, 0)
The
daily and
ticket
sales on- Chapter
the 15th day
Study
Guide
Review
4 after a movie
opens is $12.29.
Find the inverse of each relation.
52. {(1, 9), (13, 26), (–3, 4), (–11, –2)}
The inverse is {(4, -12), (0, -8), (-4, -4), (-8, 0)}.
Find the inverse of each function
56. f (x) = 3x + 8
SOLUTION: To find the inverse, exchange the coordinates of the
ordered pairs.
SOLUTION: (1, 9) → (9, 1)
(13, 26) → (26, 13)
(–3, 4) → (4, –3)
Write the final equation in slope-intercept form. So,
(–11, –2) → (–2, –11)
.
The inverse is {(9, 1), (26, 13), (4, -3), (-2, -11)}.
58. SOLUTION: 54. SOLUTION: To find the inverse, exchange the coordinates of the
ordered pairs.
Write the final equation in slope-intercept form. So, f
(–12, 4) → (4, –12)
-1
(x) = 4x + 28.
(–8, 0) → (0, –8)
60. (–4, –4) → (–4, –4)
SOLUTION: (0, –8) → (–8, 0)
The inverse is {(4, -12), (0, -8), (-4, -4), (-8, 0)}.
Find the inverse of each function
56. f (x) = 3x + 8
SOLUTION: Write the final equation in slope-intercept form. So,
.
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Write the final equation in slope-intercept form. So,
.
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