Chapter 9
Chapter
T
es
t
537
Chapter T
es
t
9
9
Solve the equation using any method. Explain yo
ur choice of method.
1.
x
2
121
0
2.
x
2
6
x
10
3.
2
x
2
+
3
x
+
7
0
4.
x
2
7
x
+
12
0
5.
5
x
2
+
x
4
0
6.
(4
x
+
3)
2
16
7.
Describe how
you can use the method of completing the square
to determine whether the function
f
(
x
)
2
x
2
+
4
x
6 can be
represented by the graph show
n.
8.
Write an expression in
vol
ving radicals in which a
conjugate can be used to simplify the expression.
Solve the system using any method.
9.
y
x
2
4
x
2
10.
y
5
x
2
+
x
1
11.
y
1
—
2
(4)
x
+
1
y
4
x
+
2
y
7
y
x
2
2
x
+
4
12.
A skier leav
es an 8-foot-tall ramp with an initial v
ertical ve
locity
of 28 feet per second. The function
h
16
t
2
+
28
t
+
8
represents the height
h
(in feet) of the skier after
t
seconds. The
skier has a perfect landing. How
many points does the skier earn?
13.
An amusement park ride lifts seated riders 265 feet abov
e the ground.
The riders are then
dropped and experience free fa
ll until the brakes are acti
vate
d 105 feet above
the ground.
The function
h
16
t
2
+
265 represents the height
h
(in feet) of the riders
t
seconds
after they are dropped. Ho
w long
do the riders experience free fa
ll? Round your solution
to the nearest hundredth.
14.
Write an expression in simplest form that represents the area
of the painting show
n.
15.
Explain how
you can determine the number of times the graph
of
y
5
x
2
10
x
+
5 intersects the
x
-axis without graphing or
solving an equation.
16.
Consider the quadratic equation
ax
2
+
bx
+
c
= 0 Find va
lues of
a
,
b
, and
c
so
that the graph of its related function has (a) two
x
x-intercepts, (b) one
x
-intercepts.
and (c) no x-intercepts.
17.
The numbers
y
of two types of bacteria after
x
hours are represented by the models below
.
y
3
x
2
+
8
x
+
20
Type
A
y
27
x
+
60
Type
B
a.
When are there 400
T
ype
A bacteria?
b.
When are the number of
T
ype
A and
T
ype B bacteria the same?
c.
When are there more
T
ype
A bacteria than
T
ype B?
When are there more
T
ype B
bacteria than
T
ype
A? Use a graph to support your answer
.
Criteria
Scoring
Maximum height
1 point per foot
T
ime in air
5 points per second
Perfect landing
25 points
x
y
3
36
in.
30
x
7
in.
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