114chris is twice as old as don, and next year the sum of their ages will be four times as much as don’s age last year. find their present ages.

Let x=Don's present age
2x=Chris's present age
next year:
x+1=Don's age
2x+1=Chris's age
(x+1)+((2x+1)=4(x-1) (next year the sum of their ages will be four times as much as Don's age last year.)
x+1+2x+1=4x-4
x=6
2x=12
Don's present age=6
Chris's present age=12