Download Skills Practice 3-7 - District 196 e

NAME ________________________________________ DATE ______________ PERIOD _____
3-7
Study Guide and Intervention
Functions and Graphs
The solution of an equation with two variables consists of two numbers, one for each variable, that
make the equation true. The solution is usually written as an ordered pair (x, y), which can be
graphed. If the graph for an equation is a straight line, then the equation is a linear equation.
Graph y 3x 2.
Example 1
Select any four values for the input x. We chose
3, 2, 0, and 1. Substitute these values for x to
find the output y.
x
2
1
0
1
3x 2
3(2) 2
3(1) 2
3(0) 2
3(1) 2
y
4
1
2
5
y
(x, y)
(2, 4)
(1, 1)
(0, 2)
(1, 5)
O
x
Four solutions are (2, 4), (1, 1), (0, 2), and (1, 5).
The graph is shown at the right.
Exercises
1. y x 1
2. y x 2
y
y
O
x
4. y 4x
O
Chapter 3
3. y x
y
x
O
5. y 2x 4
x
O
x
6. y 2x
y
y
y
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Graph each equation.
x
O
46
O
x
Course 2
3-1
3-1
Study Guide and Intervention
Writing Expressions and Equations
Writing Expressions and Equations
Write each phrase as an algebraic expression.
The table below shows phrases written as mathematical expressions.
Phrases
Expression
9 more than a number
the sum of 9 and a number
a number plus 9
a number increased by 9
the total of x and 9
Phrases
Phrases
Expression
3. twelve minus y
Expression
7. four increased by a
t
5
11. three times as many soft drinks 3s
Equation
e
3
13. Emily’s age divided by 3 ᎏᎏ
A2
n
2
3n 60 59
6. a number less eleven
4a
9. the product of c and 10 10c
The table below shows sentences written as an equation.
Sentences
4. seven less than n n 7
5. five years younger than Jessica j 5
Phrases
Sixty less than three times the amount is $59.
Three times the amount less 60 is equal to 59.
59 is equal to 60 subtracted from three times a number.
A number times three minus 60 equals 59.
12 y
x3
h4
a number divided by 5
the quotient of t and 5
divide a number by 5
6g
2. three more than x
15. a number divided by 2 ᎏᎏ
n 11
8. eight dollars more than m m 8
10. twice as many days 2d
12. t multiplied by 14
14t
24
ᎏᎏ
n
14. 24 divided by some number
15
w
16. the quotient of 15 and w ᎏᎏ
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Write each sentence as an algebraic equation.
Exercises
Write each phrase as an algebraic expression.
3
ᎏᎏ
y
1. 7 less than m m 7
2. the quotient of 3 and y
3. the total of 5 and c 5 c
4. the difference of 6 and r 6 r
5. n divided by 2
n
ᎏᎏ
2
6. the product of k and 9
9k
Write each sentence as an algebraic equation.
7. A number increased by 7 is 11. n 7 11
8. The price decreased by $4 is $29.
p 4 29
9. Twice as many points as Bob would be 18 points. 2b 18
m
10. After dividing the money 5 ways, each person got $67. ᎏᎏ 67
5
19. Four cents more than the price is 93¢.
20. Fifteen minus y is 7.
21. A number decreased by 5 is 12.
22. Five dollars less than Yumi’s pay is $124.
23. A number times four is 20.
24. Twice the number of cars is 40.
25. The product of z and 6 is 54.
26. A number divided by 6 is 12.
p 4 93
n 5 12
4n 20
x 2 10
15 y 7
y 5 124
2c 40
n
ᎏᎏ 12
6
6z 54
27. 72 divided by y is 9.
28. 175 students separated into n classes is 25.
72
ᎏᎏ 9
y
175
ᎏᎏ 25
n
2c 1 17
12. Seven less than a number is 15. n 7 15
Course 2
10
18. The sum of x and 2 is 10.
n39
29. One more than twice as many CDs is 17.
11. Three more than 8 times as many trees is 75 trees. 8t 3 75
Chapter 3
17. A number plus three is 9.
30. Four less than three times a number is 14.
3n 4 14
Course 2
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Chapter 3
11
Course 2
Answers (Lesson 3-1)
6 multiplied by g
6 times a number
the product of g and 6
1. b plus 1 b 1
Expression
4 subtracted from a number
a number minus 4
4 less than a number
a number decreased by 4
the difference of h and 4
x9
Skills Practice
Lesson 3–1
Chapter 3
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