input: from typing import Tuple
  
  def linear_eq(a: float, b: float, c: float, x: float, y: float) -> float:
      """ Calculate the objective function of a linear equation given the coefficients and variables.
      >>> linear_eq(3, 5, 7, 2, 1)
      6.0
      >>> linear_eq(1, -1, 0, 3, 3)
      0.0
      """
      return a * x + b * y - c
output:     return a * x + b * y - c