-------------------------------------------------- Define x : -------------------------------------------------- Let Cheryl be x years old. Cheryl = x Lisa = x + 6
-------------------------------------------------- In two years time: -------------------------------------------------- Cheryl = x + 2 Lisa = x + 8
-------------------------------------------------- Lisa will be twice as old as Cheryl : -------------------------------------------------- x + 8 = 2(x + 2)
-------------------------------------------------- Solve x : -------------------------------------------------- x + 8 = 2(x + 2) x + 8 = 2x + 4 x = 4
-------------------------------------------------- Find their age : -------------------------------------------------- Cheryl = x = 4 Lisa = x + 6 = 4 + 6 = 10
-------------------------------------------------- Answer: Lisa is 10 years old now. --------------------------------------------------