Name
LESSON
2-5
Date
Class
Practice A
Solving for a Variable
Answer each of the following.
1 relates the period of
2. The formula T __
f
a sound wave T to its frequency f.
1. The formula K C 273 is used to
convert temperatures from degrees
Celsius to Kelvin. Solve this formula
Solve this formula for f.
for C.
1
f __
T
C K 273
Solve each equation for the variable indicated.
3. x 5y for y
4. s 4t r for s
x
y __
5
6. 6 hj k for j
k
j 6_____
h
s r 4t
v
7. __
w 9 for w
v
w __
9
5. 3m 7n p for m
p 7n
m _______
3
3 c for a
_____
8. a
b
a bc 3
Answer each of the following.
9. The formula d rt relates the distance an
object travels d, to its average rate of speed r,
and amount of time t that it travels.
a. Solve the formula d rt for t.
b. How many hours would it take for a car
to travel 150 miles at an average rate of
50 miles per hour?
d
t __
r
3
10. The formula F E V 2 relates the number of
faces F, edges E, and vertices V, in any convex
polyhedron.
a. Solve the formula F E V 2 for F.
F2EV
b. How many faces does a polyhedron with
20 vertices and 30 edges have?
12
Copyright © by Holt, Rinehart and Winston.
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Holt Algebra 1
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