MATH 115 Practice Test #3 (Chapter 5)
1. Simplify:
24 x 3 y 7
a.
8 xy 4
c.
2n 2  8n
4n
e.
x 2  36
6 x
b.
2 x  12
x  x  30
d.
n 2  11n  18
n 2  9n  22
2
2. Perform the operation and write in simplest form:
y2 −4y
y3
( x  1) 2 x 2  4
a.
∙
b.

y4
y2 −3y−4
( x  2) 2 x 2  1
c.
x2  4x
x3  7x2

x 2  x  20 x 2  13x  40
5 x  15 x 2  x  12

d.
3x  6 x 2  7 x  10
3. Subtract:
5
2
a.
–
2
x  17 x
9x
4. Solve:
x
3
3
 
a.
x 3 2 x 3
5. Simplify the complex fractions:
2 3

x y
a.
5 2

x y
9
x
c.
81
1  2
x
b.
x 2  15 x 54

x 9
9 x
b.
x 1
3
12
  2
x3
x x  3x
b.
1 
d.
1
y
 2
2x 2x
1 y

4 4x
3
4

2
2x
x
5
7
 2
3x
x
c.
c.
2
5
 2
x  x  6 x  5x  6
2
3
7

x7 x5
6. It takes you 30 hours to build a website. Your friend can build the same website in 20 hours.
Working together, how long will it take the team to build a website?
7. Rob can run 27 mi in the same time it takes Mike to run 15 mi. If Rob runs 4 mi/h faster
than Mike, find Mike’s speed.
8. The tax on a property with an assessed value of $130,000 is $1,440. Find the tax on a
property with an assessed value of $250,000 (round to the nearest cent).