Prove that the following vertices form a parallelogram.
 
\(A = (\)10, 10\()\), \(B = (\)40, 36\()\), \(C = (\)78, 12\()\) and \(D = (\)48, 28\()\).
 
Figure 13.png
 
Mid-point of diagonal \(AC\): \((\), \()\)
 
Mid-point of diagonal \(BD\): \((\), \()\)