Answer:
4 is not the constant. 2 is.
Explanation:
In the following equation: y = 4x + 2
x and y are variables. x can be any given number, and y would be the resulting answer.
4 is not the constant, because the product it will produce varies on what x will be.
2 is a constant, because it will not change regardless what is put into x. It will continue to stay as 2.