See Problem 5.
Choose the correct factored form for each expression.
-
k
2
+
5
k
n
−
84
n
2
k squared , plus 5 k n minus 84 , n squared
-
(
k
−
7
n
)
(
k
−
12
n
)
open k minus 7 n close open k minus 12 n close
-
(
k
−
7
n
)
(
k
+
12
n
)
open k minus 7 n close open k plus 12 n close
-
p
2
−
8
p
q
−
33
q
2
p squared , minus 8 p q minus 33 , q squared
-
(
p
+
3
q
)
(
p
−
11
q
)
open p plus 3 q close open p minus 11 q close
-
(
p
−
3
q
)
(
p
+
11
q
)
open p minus 3 q close open p plus 11 q close
-
x
2
−
16
x
y
+
48
y
2
x squared , minus 16 x y plus 48 , y squared
-
(
x
−
4
y
)
(
x
+
12
y
)
open x minus 4 y close open x plus 12 y close
-
(
x
−
4
y
)
(
x
−
12
y
)
open x minus 4 y close open x minus 12 y close
Factor each expression.
-
r
2
+
19
r
s
+
90
s
2
r squared , plus 19 r s plus 90 , s squared
-
g
2
−
12
g
h
+
35
h
2
g squared , minus 12 g h plus 35 , h squared
-
m
2
−
3
m
n
−
28
n
2
m squared , minus 3 m n minus 28 , n squared
-
x
2
+
3
x
y
−
18
y
2
x squared , plus 3 x y minus 18 , y squared
-
w
2
−
14
w
z
+
40
z
2
w squared , minus 14 w z plus 40 , z squared
-
p
2
+
11
p
q
+
24
q
2
p squared , plus 11 p q plus 24 , q squared
B Apply
-
Writing Suppose you can factor
x
2
+
b
x
+
c
x squared , plus b x plus c as
(
x
+
p
)
(
x
+
q
)
.
open x plus p close open x plus q close .
- Explain what you know about p and q when
c
>
0
.
c greater than 0 .
- Explain what you know about p and q when
c
<
0
.
c less than 0 .
-
Error Analysis Describe and correct the error made in factoring the trinomial.
-
Think About a Plan The area of a parallelogram is given by the trinomial
x
2
−
14
x
+
24
.
x squared , minus 14 x plus 24 . The base of the parallelogram is
x
−
2
.
x minus 2 . What is an expression for the height of the parallelogram?
- What is the formula for the area of a parallelogram?
- How can you tell whether the binomial that represents the height has a positive or negative constant term?
-
Recreation A rectangular skateboard park has an area of
x
2
+
15
x
+
54
.
x squared , plus 15 x plus 54 . What are the possible dimensions of the park? Use factoring.
Write the standard form of each polynomial modeled below. Then factor each expression.
-
-
-
Reasoning Let
x
2
−
13
x
−
30
=
(
x
+
p
)
(
x
+
q
)
.
x squared , minus 13 x minus 30 equals open x plus p close open x plus q close .
- What do you know about the signs of p and q?
- Suppose
|
p
|
>
|
q
|
.
vertical line p vertical line greater than vertical line q vertical line . Which number, p or q, is a negative integer? Explain.
-
Reasoning Let
x
2
+
13
x
−
30
=
(
x
+
p
)
(
x
+
q
)
.
x squared , plus 13 x minus 30 equals open x plus p close open x plus q close .
- What do you know about the signs of p and q?
- Suppose
|
p
|
>
|
q
|
.
vertical line p vertical line greater than vertical line q vertical line . Which number, p or q, is a negative integer? Explain.