Answer:
 2 a
Explanation:
Possible derivation: 
d/dx(2 a x + 2 a y) 
 
Differentiate the sum term by term and factor out constants: 
 = 2 a (d/dx(x)) + d/dx(2 a y) 
 
The derivative of x is 1: 
 = d/dx(2 a y) + 1 2 a 
 
The derivative of 2 a y is zero: 
 = 2 a + 0 
 
Simplify the expression: 
Answer: 2 a