Ответ:

  1. \(x + 19 = -4\)
    \(x = -4 - 19\)
    \(x = -23\).
  2. \(5x - 8 = -23\)
    \(5x = -23 + 8\)
    \(5x = -15\)
    \(x = -3\).
  3. \(-7x + 12 = 40\)
    \(-7x = 40 - 12\)
    \(-7x = 28\)
    \(x = -4\).
  4. \(2(y - 6) - (-3y) = 8\)
    \(2y - 12 + 3y = 8\)
    \(5y = 20\)
    \(y = 4\).

Ответ: а) \(x=-23\); б) \(x=-3\); в) \(x=-4\); г) \(y=4\).