Expert: Lynn Houston - 7/21/2010

Question
1. Solve the system:  x + y = 4 (y + 2)
                     x - y = 2 (y + 4)

a. Infinite solutions    b. (3,8)
c. No solution           d. (8,3)

2. Solve the system to find (u,v).  Hint:  x = 1/u and y = 1/v.  Use x and y in the equations to solve.  Once you solve for x and y, set those solutions equal to 1/u and 1/v, respectively, to find (u,v): 6/u + 5/v = 1
            3/u - 10/v = 3
a.(1/3,-1/5) c.(-3,5)  
b. (3,-5)    d. (1/5,-5)

3. Solve the system to find (u,v).  Hint:  x = 1/u and y = 1/v.  Use x and y in the equations to solve.  Once you solve for x and y, set those solutions equal to 1/u and 1/v, respectively, to find (u,v): 3/u + 4/v = 1
           6/u - 2/v = 1
a. (5,10)      c.(1/5,1/10)
b. (1/3,7/5)   d.(10,5)

4.Solve the following system: 2x + y = -3
                             x + 3y = 1

5. Solve the following system:
3x - y = 4
x + 2y = -8

6. Solve the following system: 5x + 2y = 7
                              x - y = 7

Answer
1. Solve the system:  x + y = 4 (y + 2)
                    x - y = 2 (y + 4)

a. Infinite solutions

2. Solve the system to find (u,v)
6/u + 5/v = 1
3/u - 10/v = 3

b. (3,-5)    

3. Solve the system to find (u,v)
3/u + 4/v = 1
6/u - 2/v = 1

a. (5,10)  

4.Solve the following system:
2x + y = -3
x + 3y = 1

-5y = -5
y = 1, therefore x = -2


5. Solve the following system:
3x - y = 4
x + 2y = -8

-7y = 28
y = -4, therefore x = 0

6. Solve the following system:
5x + 2y = 7
x - y = 7

7y = -28
y = -4, therefore x = 3