If I give my brother 5 dollars, then we will have the same amount of money. If instead, he gives me 14 dollars, then I'll have twice as much money as he will have. How much money does my brother currently have (in dollars)?
Y = your money
B = your brother's money
Initially Y = B
Y - 5 = B + 5 → Y = B + 10 (1)
Y + 14 = 2 (B - 14) (2)
Sub (1) into (2)
( B + 10) + 14 = 2 (B - 14)
B + 24 = 2B - 28 rearrange as
24 + 28 = 2B - B
52 = B
Your brother has $52
