Name ________________________________________ Date __________________ Class__________________
LESSON
3-3
Practice C
Solving for a Variable
Answer each of the following.
1. The formula P 2l 2w relates the
perimeter P of a rectangle to its length l
and width w. Solve this formula for w.
vf v i
is used to find an
t
object’s acceleration given initial velocity
vi, final velocity vf, and time t. Solve this
formula for vf.
2. The formula a
_________________________________________
________________________________________
Solve each literal equation for the indicated variable.
3. 3f
g for f
4. 12
________________________
6. 5h g
a 5b for a
5. 3x 7y
_________________________
jk for h
7.
________________________
r
s
t 9 for r
________________________
8.
_________________________
z for x
m3
n
p for n
________________________
Answer each of the following.
9. The formula F ma relates the force F exerted
on an object, to the object’s mass m, and
acceleration a.
a. Solve the formula F
ma for a.
____________________________________
b. Suppose a shot-putter exerts a force of
123.5 kg • m/s2 on a shot that has a mass of
6.5 kg. What is the rate of acceleration of
the shot? (The answer will be in m/s2.)
____________________________________
10. The formula I Prt can be used to determine the
interest I that is earned on a principal amount of
money P, when the money is invested at an annual
percentage rate r for t years.
a. Solve the formula I
Prt for t.
____________________________________
b. If a couple invests $5000 in an account that
earns a 3% interest rate, how long will they
need to invest it to earn $1200 in interest?
(Hint: Convert the interest rate to a decimal.)
____________________________________
© Houghton Mifflin Harcourt Publishing Company
67
Holt McDougal Coordinate Algebra
Reading Strategies
7. r
1. Look for an opportunity to use the
Distributive Property.
3. Collect the variable terms on one side of
the equal sign.
6
6. t
2
5. x
x
5
p 7n
3
3. y
5. m
v
9
7. w
d
r
9. a. t
b. 3
2. f
3. c
5. p
q 5r
2
7. b
a
c
c 215
5
9. a. p
b. 17
4. s
r 4t
1. w
b. 8 years
1. s
P
4
2. b
3. K
VP
T
4. w
180 a – c
3V
lh
6. j
6k
h
8. a
bc 3
7. multiply both sides by 2
8. add 3r to both sides
9. a
11. m
c
3b
10. z
3(y x)
pn 3
Challenge
2EV
10. a. F
1. l
375
2. P
3. t
5 years
4. r
0.032 or 3.2%
6. 3 years
7. $2200
8. 0.03 or 3%
2. m
4. n
8 6m
11. 0.027 or 2.7%
6. x
10 z
y
Problem Solving
8. j
h4
k
10. a. b
9. $247
1. r
2A
h
b. 32 mm
2000
5. $351
y b
x
10. 5 years
d
t
2. 9.1 m/s
3. 8.5 m/s
4. 0.4 m/s
5. B
6. F
7. D
8. J
Reading Strategies
Practice C
P 2l
2
I
Pr
6. add –x to both sides
Practice B
1. r
10. a. t
5. 12 in.
1
T
b. 12
C
2S
d
4
m3
p
Review for Mastery
1
Practice A
K 273
8. n
b. 19 m/s2
3-3 SOLVING FOR A VARIABLE
1. C
F
m
9. a. a
2. Combine any like terms.
4. p
s(t 9)
1. Possible answer: 3x 2y
9
2. vf
at vi
2. The equation contains only one
variable, n.
3. Yes, because it has two or more
variables.
3. f
g
3
4. a
12 5b
5. x
z 7y
3
6. h
jk g
5
4. Divide both sides by r.
© Houghton Mifflin Harcourt Publishing Company
A9
Holt McDougal Coordinate Algebra