input: Write a python function to solve a linear equation system.
  assert solve_linear_equation_system(2, 3, 10) == (2.0, 2.0)
  assert solve_linear_equation_system(1, 1, 4) == (2.0, 2.0)
  assert solve_linear_equation_system(4, 2, 12) == (3.0, 3.0)
output: def solve_linear_equation_system(a, b, c):
      # Check if the system of equations is consistent and has a unique solution
      if a == 0 and b == 0:
          raise ValueError("Both coefficients cannot be zero.")
      
      # Calculate the solution for the system of equations
      x = c / (a + b)
      y = c / (a + b)
      
      return (x, y)