1.given f (x) = 4x – 5, find f (1) substitute f (1) = 4(1) – 5 simplify f (1) = 4 – 5 f (1) =...
TRANSCRIPT
Algebra I Concept Test # 6 – Functions Practice Test
1. Given f (x) = 4x – 5, find f (1)
Substitutef (1) = 4(1) – 5
Simplifyf (1) = 4 – 5
f (1) = −1 Simplify
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0
2. Given the following graph,
Algebra I Concept Test # 6 – Functions Practice Test
a) find f (− 3)
b) find f (0)
f(x)
− 3
0
=
=
0
33
Note: You are looking for the y-coordinate when x is the given value.
x f(x)
− 1
0
1
3. a) Write the following equation in function notation:
y = 3x – 2f(x) = 3x – 2
c) Graph:
− 5
− 2
1
f(1) = 3 – 2 (1)
f(1) = – 2 (3)
f(1) = 1
− 1
0
1
f(0) = 3 – 2 (0)
f(0) = – 2 (0)
f(0) = − 2
f(−1) = 3 – 2 (−1)
f(− 1) = – 2 (− 3)
f(− 1) = − 5
( − 1, −5)
( 0, − 2)
( 1, 1)
f(x)
b) Using a table find 3 points that are solutions.
Algebra I Concept Test # 6 – Functions Practice Test
(− 1, − 5)
(0, − 2)
(1, 1)
C(0) = + 15(0)
C(0) = 15
C(15) = 5 + 15 (15)C(10) = 5 + 15 (10)
C(10) = + 15 (50)
C(0) = 5 + 15 (0)x C(x)
0
10
15
4. The cost of your New Year’s Eve party is $15.00 for the cake and $5.00 per person for party favors.
a) Write the cost function based on the number of people attending.
C(x) = 5x + 15
Algebra I Concept Test # 6 – Functions Practice Test
Note: x is the number of people who attend and
C(x) is the cost of the party.b) Using a table to find 3 points, graph the
function, clearly label the intervals and axes.
15
65
90
C(15) = + 15 (75)
C(15) = 90
0
10
15C(10) = 65
C(x) = 5x + 15
d) At the y-intercept, determine the number of people
who attend your party.
x C(x)
0
10
15
4. b) Graph the function clearly label the intervals and axes.
Algebra I Concept Test # 6 – Functions Practice Test
15
65
90
x (5)
C(x) (10)
0 5 10 15 20 25 30 35 40 45 50 55
120110100 90
80 70 60 50
40 30
20 10
(0, 15)
(10, 65)
(15, 90)
c) Determine the “rate of change.”
$ 5 per person
None
Note: The rate of change
is the slope.
x C(x)
0
10
15
4. b) Graph the function clearly label the intervals and axes.
Algebra I Concept Test # 6 – Functions Practice Test
15
65
90x (5)
C(x) (10)
0 5 10 15 20 25 30 35 40 45 50 55
120110100 90
80 70 60 50
40 30
20 10
e) Find the cost if 55 people attended.
C(55) = 5 + 15 (55)
C(55) = + 15 (275)
C(55) = 290$ 290.00
C(x) = 5x + 15
g) Identify whether the cost or the number of people represent the independent variable.
4.continued
Algebra I Concept Test # 6 – Functions Practice Test
x (5)
C(x) (10)
0 5 10 15 20 25 30 35 40 45 50 55
120110100 90
80 70 60 50
40 30
20 10
f) Find the number of people who
attended if the cost of the party was $415.00.
C(x) = 5x + 15
(415) = 5x + 15
400 = 5x
80 people
# of people
80 = x STAY
POSITIVE!