Let's set up some variables here. Let x be your money, and b be your brother's money.
If you give your brother five dollars, the equation will be x - 5 = b + 5.
However, if your brother gives you 14 dollars, you can set up the equation x + 14 = 2(b-14) because you have twice as much as him.
Now we have the system of equations:
x - 5 = b + 5
x + 14 = 2(b - 14) = 2b-28 ==> x + 14 = 2b - 28
Using substitution in the first equation, x = b + 10. Now we can solve for b:
b + 10 + 14 = 2b - 28 ==> b + 24 = 2b - 28
Subtract b on both sides and add 28 and get:
52 = b. Therefore, your brother has 52 dollars.