Name ________________________________________ Date ___________________ Class __________________
LESSON
12-2
Practice C
Exponential Functions
1. If a golf ball is dropped from a height of 25 feet, the function
x
§ 2·
f(x) 25 ¨
gives the height in feet of each bounce.
© 3 ¹̧
What will be the height of the golf ball on the 6th bounce?
Round to the nearest tenth of a foot.
_____________________________
Tell whether each set of ordered pairs satisfies an exponential
function. Explain your answer.
½°
°­§ 3 · § 1 · § 1 ·
2. ®¨ 0, , ¨ 1,
, ¨ 2, , ( 3, 0 ) ¾ _______________________________________________________
°̄© 4 ¹̧ © 2 ¹̧ © 4 ¹̧
¿°
_________________________________________________________________________________________
3. {(0, 3), (1, 7.5), (2, 18.75), (3, 46.875)} __________________________________________________
_________________________________________________________________________________________
4. {(3, 7.5), (6, 6), (9, 4.8), (12, 3.84)} ______________________________________________________
_________________________________________________________________________________________
Graph each exponential function.
5. y
3(2.5)
x
6. y
0.5(3.5)
x
The Mendez family bought two used cars: one domestic
and one foreign. The domestic car was purchased for
$11,600. The foreign car was purchased for $9700. The
functions in the table represent the value of each car x
years from now due to depreciation.
8. How much is each car worth 2 years from now?
7. y
§ 1·
2 ¨ ¸
©5¹
x
Domestic
f (x) 11,600 (0.88)x
Car
Foreign
f (x) 9700 (0.93)x
Car
___________________________
___________________________
9. In how many years will the foreign car be worth more than the domestic car? ______________
© Houghton Mifflin Harcourt Publishing Company
291
Holt McDougal Coordinate Algebra
8.
7.
8. domestic: $8983.04; foreign: $8389.53
9. 2014
9. 4 years
10. 2019
Review for Mastery
Practice C
1. 2.2 feet
1. yes
2. no
2. no, as the x-values increase by 1,
the y-values are not multiplied by a
constant amount.
3. yes
4. 1.6 feet
3. yes, as the x-values increase by 1,
the y-values are multiplied by 2.5.
x
5. |1601
6.
2
4. yes, as the x-values increase by 3,
the y-values are multiplied by 0.8.
1
0
5.
y
y
y
y
4(0.5)x
y
4(0.5)
2
16
4(0.5)
1
8
4(0.5)
0
4
1
2
1
y
4(0.5)
x
y
2(5)x
6.
7.
1
0
1
2
y
y
y
y
y
1
0.4
2(5)
0
2
2(5)
1
10
2(5)
2
50
2(5)
© Houghton Mifflin Harcourt Publishing Company
A65
Holt McDougal Coordinate Algebra