Problem 58-60
First write a system of equations (don't forget to define your variables).
Then, write the system in matrix form.
Apply the Gauss-Jordan method. If you have a calculator availabe, this is a good
time to use it.
Finally, use this result to state a solution (in words).
See Example 5.
Note: Homework Hints are given only for the levels 1 and 2 problems.