input: from typing import Tuple
  
  def calculate_objective_function(a: float, b: float, c: float, x: float, y: float) -> float:
      """ Calculates the objective function of a linear equation of the form ax + by = c.
      >>> calculate_objective_function(3.0, 5.0, 7.0, 1.0, 1.0)
      1.0
      >>> calculate_objective_function(3.0, 5.0, 7.0, 0.0, 1.4)
      0.0
      """
      return a * x + b * y - c
output:     return abs(a * x + b * y - c)