Math 112   Test 1    10 pts each          Jan. 27, 2005


Solve for x:

 

1.   5x + (3x - 4 ) + 2 = 5 - 2(3x + 2)

 

 

2.    

 

 

3.    

 

 

4.   Solve for d

 

an = a1 + (n-1)d

 

Solve the system of equations

 

5.   2x - y = 16

     x + 3y = 1

 

 

6.   2x - y = 4

     6x  - 12 = 3y

 

 

7.  Let A = {1, 2, 3, 4 }

     Let B = {2, 4, 6,8}

     Let U = Universe = {1,2,3,4,5,6,7,8,9,10}

 

Write the indicated set.

a.  A ² B

 

 

 

b. AĠ ³ B

 

 

8.  Solve the linear inequality. Leave the answer in inequality notation.

 

3x - 2 ² 4(x + 2) - 5

 

9.  Solve the linear inequality.  Put the answer in Interval notation.

 

6 ³ 2(1 - 3x)  > 0

 

 

10.    Solve the absolute value inequality.  Leave the answer in algebraic notation.

 

| 3 - 2x | ² 4

 

 

Bonus:  5 points !

 

If a and b are negative numbers and b/a is greater than 1, then is a-b positive or negative?

 (You must prove your answer!)