Your cousin is 8 years older than your brother. three years ago, your cousin was twice as old as your brother. how old is your cousin now? how old is your brother now?

Your brother is now 11. If your brother is 3, you put '8+x'=x+5 to get your cousins age. Once you have x+5, set it equal to 2(x-3) and solve that. You should get x+5=2x-6 and you get x=11. You add 8 to get your cousins age. So your brother is 11 and your cousin is 19.