I have this question on my homework and I don't know how to do it.
On my math homework the question is: The sum of ages of all four members of Alyssa's family (her mom, dad, Alyssa and her younger brother) is 90 years. Her dad is 2 years older than her mom, Alyssa is 4 years older than her brother. Ten year ago the sum of their ages was 51 years. How old is each of them now?
Help me please.