David's age is four times Alisa's age. In eight years, David will be twice as old as Alisa. How old is each now?

David is 16 years old.

Alisa is 4 years old.

Alissa's current age = 4

David's current age = 16

Step-by-step explanation:

if say Alissa is x years old then David is 4x years old

in 8 years Alissa will be x+8, and David 4x+8 and that's twice as Alissa's age therefore:

2 * (x+8) = 4x+8

2x+16 = 4x+8

16-8=4x-2x

8=2x

x=4