bit of maths problem

Question

output 2,4,6

basic maths but i just seem to be able to get the correct numbers to get the output

 

using System;

namespace HelloWorld
{
class Program
{
static void Main(string[] args)
{
int a, b, c;

a = -1;
b = -2;
c = 2;

b = 2 * a * b;
a = (c - b) * 2;
c = a + b;
Console.Write(a + ", " + b + ", " + c);
}
}
}