To solve this problem, we can write a system of linear equations using the given information and then use Gaussian elimination to find the solution.
To write a system of linear equations for this problem, we can use the following variables: x for the number of hours worked at job A, and y for the number of hours worked at job B.
We know that the total number of hours worked per week is 57, so we can write the equation:
x + y = 57
Next, we can use the pay rates to create the second equation.
Mike earns $8 per hour at job A, so the amount of money earned from job A is 8x.
Similarly, he earns $5 per hour at job B, so the amount of money earned from job B is 5y.
The total pay for the week is $474, so we can write the equation:
8x + 5y = 474
Now, we can solve this system of linear equations using Gaussian elimination or another method to find the values of x and y.
By solving the system of equations, we find that Mike works 39 hours at job A and 18 hours at job B.